Cadillac Owners Forum banner
  • Hey everyone! Enter your ride HERE to be a part of September's Ride of the Month Challenge!
1 - 20 of 29 Posts

·
Registered
'07 SRX
Joined
·
69 Posts
Discussion Starter · #1 ·
Just received a letter from Cadillac about the early 07 timing chains. Anyone else get one?
 
G

·
just received a letter from cadillac about the early 07 timing chains. Anyone else get one?

got the letter also. Have an 08 mfg dec 2007. Timing chains replaced at 35,000. I change oil at the 50% point on the oil calibration system.
Then again at o to 5 %. . I still like to go by milage on oil. I think they should give us a free oil change when they recalibrate the module. Gm did make a profit this year thanks to srx sales.
 

·
Registered
2009 SRX-4 Sport / TriCoatWhite
Joined
·
1,185 Posts
I got my letter yesterday,

It says:

-----------------------------------------------------------------------------------------------
Dear XXXXX;

This notice is sent to inform you that General Motors is conducting a Customer Satisfaction Program that affects 2009 model year Cadillac SRX vehicles equipped with a V6 engine.

Your vehicle was designed and built to meet GM's high standards for quality and reliability. However, we have determined that under certain driving conditions, and with extended oil change intervals, the timing chain would wear prematurely and cause the illumination of the Service Engine Soon light. Timing chain wear can be affected by the age of the engine oil and driving conditions.

What we will do: To ensure that your vehicle will not experience this condition, your Cadillac dealer will change the calibration of the engine control module, including the engine oil life monitor, which in most cases will recommend more frequent oil changes. This service will be performed for you at no charge until February, 28, 2013.


What you should do: To limit any possible inconvenience, we recommend that you contact your Cadillac dealer as soon as possible to schedule an appointment for this repair.

If you have any questions or need assistance, just contact your dealer or the Cadillac Customer Assistance Center at 1.866.982.2339 (TTY 1.800.833.2622).

We sincerely regret any inconvenience or concern that this situation may cause you. We want you to know that we will do our best throughout your ownership experience, to ensure that your Cadillac SRX provides you with many miles of enjoyable driving.

Jim Maloney
General Director - Customer & Relationship Services
-----------------------------------------------------------------------------------------------

So - - in essence, they are going to de-tune your engine to put less stress on the timing chain, and want you change your Moble1 Oil more often. Now if the de-tune increases gas mileage, I am good with that... but for some reason, I am thinking that won't be the case.

GM replaced my timing chain on my 09 at 27k miles.

However: a good thing out of this is: if you change your oil more often - the fact that our SRX's lose oil will have less of an impact.

I contend, all this will really do is delay the inevitable. The problem is a design engineering problem, not an oil and engine tune issue... This is a work-a-round, not a fix, and they still going to have timing chain problems. Only maybe now every 50k miles instead of 30k miles. Of course - GM is hoping that making this maintenance adjustment will extend the timing chain life span out past the warranty period so GM will avoid paying for all those timing chain repairs.

I wish them luck.
 

·
Registered
2007 SRX4 N*, 2004 Infinity G35 Coupe
Joined
·
2,005 Posts
I agree, PROF. In my mind cutting the oil change interval in half will have no positive impact on the life of the timing chains for those driving under "normal use" conditions and who keep their oil levels up to snuff, which is probably most of us here on this forum.

Some of us already change out motor oil @ 7K to 8K miles, around 50% on the OLM. And timing chains failed. What good did that do? Yet there have been other posters who admitted their oil levels got low enough to witness their engines running poorly.

On another thread a poster noted he doubts dealer claims that a significant number of the timing chain failures are due to running the V6 with seriously low oil levels. While I think the jury is out on that one, my Dad used to say that "you and I are not we." His meaning in this case, the masses do not check their motor oil level regularly, keep it up to snuff, let alone change it at the appropriate time and/or mileage intervals.

A friend of mine who works at a Caddy dealer says that the number of vehicles that show up at his dealership for service and have seriously low oil levels would surprise me. Others, he said, show up with motor oils that appear well beyond the recommended change interval. My private mechanic agrees with the friend.

And while waiting at the latter's business while getting my fluids swapped out some months ago, two different folks pulled in because their "light" came on.......both were several quarts low, with no reading on the dipstick. That was 2 in just an hour's time.

Personally, I think by and large the V6 SRX timing chains have been and are bad out of the box or that the engine design for their lubrication is faulty, engineered incorrectly. Too many anal retentive guys like me on this forum have had premature timing chain failure to make me believe oil levels and change intervals are at the core of the timing chain failure problem. Even after timing chain redesigns from model years 2007-2009. And motor oil experts on the internet, one after another, claim there is NO benefit to swapping out perfectly good motor oil with an early oil change, that the manufacturers recommended change intervals are perfectly safe.

Where does all this leave us? In my mind, it is swapping out perfectly good motor oil for absolutely no benefit and possibly a detune to take stress off the faulty chains, which still may or may not be oiled properly due to an engineering flaw.

I feel bad for the V6 members here that have this issue hanging over their head. A warranty or warranty extension may provide some peace of mind from a financial standpoint. But it doesn't provide any peace of mind when an SRX owner is wondering if today is the day they or their loved ones might not make it to work.

PJ
 

·
Registered
2007 SRX4 N*, 2004 Infinity G35 Coupe
Joined
·
2,005 Posts
Everyone with the FirstGen V6...........please read this post from Zippy in the thread "V6 Timing chain-related recall."

_______________________________________________________________________________________________________


Re: V6 timing chain-related recall.
Yeah, I wish there was more specifics to the recall, but I doubt we'll get more info any time soon... and we may be debating the root causes of the timing chain issue for years to come.

And since the OLM system was brought up I thought I would re-post this quote from the forum's old guru. It's a really good description of the OLM system and in my opinion should be required reading for every forum member.
"One thing I can touch on and clear up.....the GM oil life monitor operation and my statement that ZDP (or ZDDP as you tend to call it here...most of the API literature just sticks to ZDP so I tend to use that) depletion is the basis for oil deterioration.

My spelling is poor but ZDP stands for zinc dialkyldithiophosphate which , as it sounds, is an anti-wear compound comprised of zinc and phosphorus.

ZDP is dispersed in the oil so as to be at a potential wear site if a surface asperity happens to break thru the oil film thickness causing the dreaded metal-to-metal contact. A molecule of ZDP must be present at that moment to prevent microwelding at the contact site which will cause material transfer, scuffing, scoring, wear and catostrophic failure. The concentration of ZDP in the oil will determine if there is ZDP present to work it's magic. The greater the concentration...the more likely a molecule of ZDP will be there...and vice versa.

By nature, ZDP is sacrifical. As ZDP is "used up" at a wear site to prevent micorwelding the concentration of ZDP decreases.... So...if you measure the ZDP concentration in engine oil in a running engine it will decrease at linear rate based on engine revolutions. Any given engine has a certain number of high potential wear areas where metal-to-metal contact could occur due to reduced film thickness and/or surface asperities....areas such as rubbing element cam followers, distributor gears, rocker arm pivots, push rod tips, etc...... The more of these areas the more ZDP depletion. The more often these features come in contact the greater the ZDP depletion. That is why, generally speaking, ZDP concentration in the oil, for any given engine, will decrease at a fairly linear rate when plotted versus cummulative engine revolutions. The more times it turns the more contact the more chance for wear the greater the depletion. This is as much of a fact as I could quote ever and is really not speculation or anything. It is proven beyond a shadow of a doubt in many studies. That is why it is ONE of the basis for determining oil life remaining and why it is THE basic premis of the GM oil life algorithm. It is only ONE of the things that determines oil life...but it is the one thing that can be tied to engine operation in a linear fashion and estimated very accurately by accumulating engine revolutions via a counter.

The GM engine oil life monitor counts engine revolutions and accumulates the number for the basis of the oil life calculation. It then adds deterioration factors for operating temperature, start up temperature, soak times, ambient, coolant temperature, etc... There are a LOT of factors that "adjust" or affect the slope of the deterioration but the fundamental deterioration is traced back to the ZDP depletion that is inescapable with engine revolutions. The specific rate of ZDP depletion is readily measurable for any given engine so that is the fundamental item that is first calibrated for the oil life algorithm to tailor it specifically to that engine. <<<< does that paragraph get anyone else excited besides me? laugh.gif

You would obviously like to get the oil out of the engine before the ZDP concentration gets so low that it is ineffective at being at the right place at the right time and preventing engine wear so that becomes the long term limit on oil life for that application.

The other things that determine oil life such a acid build up, oxidation, petane insuluables such as silicon from dust/dirt, carbon or soot build up from the EGR in blowby, water contamination, fuel contamination, etc.... are all modeled by the multipliers or deterioration factors that "adjust" the immediate slope of the line defined by the engine revolution counter as those items can be modeled in other ways and accounted for in the immediate slope of the ZDP depletion line.

The algorithm was developed over the course of many years by several lubrication experts at GM Fuels and Lubes, spearheaded by Doctor Shirley Schwartz who holds the patents (with GM) for the algorithm and the oil life montitor. I had the luck of working directly with Dr. Schwartz when the idea of the oil life monitor first progressed from the theoretical/lab stage to real world testing/development/validation. There were fleets of cars operated under all conditions that deteriorate the oil life for any and every reason and , thru oil sampling and detailed analysis of the oil condition, the algorithm was developed, fine tuned and validated to be the most accurate way invented yet to recommend an oil change interval by. As just one example, I have seen cars driven side-by-side on trips, one towing a trailer and one not, for instance, to prove the effectiveness of the oil life monitor in deteriorating the oil at a faster rate just because of the higher load, higher average RPM, higher temps, etc...and it works flawlessly.

The oil life monitor is so effective because: it is customized for that specific vehicle/engine, it takes everything into account that deteriorates the oil, it is ALWAYS working so as to take into account THAT INDIVIDUALS driving schedule, and it tailors the oil change to that schedule and predicts, on an ongoing basis, the oil life remaining so that that specific individual can plan an oil change accordingly. No other system can do this that effectively.

One thing is that I know personally from years of testing and thousands of oil analysis that the oil life algorithm works. There is simply no argument to the contrary. If you don't believe me, fine, but, trust me, it works. It is accurate because it has been calibrated for each specific engine it is installed on and there is considerable testing and validation of the oil life monitor on that specific application. NOt something that oil companies or Amsoil do. They generalize....the oil life monitor is very specific for that application.

Oil condition sensors in some BMW and Mercedes products are useful, also. They have their limitations, though, as they can be blind to some contaminates and can, themselves, be contaminated by certain markers or constituents of certain engine oils. Oil condition sensors can only react to the specific oil at that moment and they add complexity, cost and another potential item to fail. One other beauty of the GM oil life monitor is that it is all software and does not add any mechanical complexity, mass, wiring or potential failure mechanism.

There is considerable safety factor in the GM oil life monitor. Typically, I would say, there is a 2:1 safety factor in the slope of the ZDP depletion curve....in other words, zero percent oil life per the ZDP depletion is not zero ZDP but twice the concentration of ZDP considered critical for THAT engine to operate under all conditions reliably with no wear. This is always a subject of discussion as to just how low do you want the ZDP to get before the oil is "worn out" if this is the deciding factor for oil life. We would tend to be on the conservative side. If the oil life is counting down on a slope that would recommend a 10K change interval then there is probably 20K oil life before the ZDP is catostrophically depleted....not that you would want to go there...but reason why many people are successful in running those change intervals.

Please...NOT ALL ENGINES ARE THE SAME. The example above is an excellent practical justification of why you would want to add EOS and change the 15W40 Delvac in the muscle car at 3000 miles max and yet can run the Northstar to 12500 easily on conventional oil. You must treat each engine and situation differently and what applies to one does not retroactively apply to others. This is where Amsoil falls short in my book by proposing long change intervals in most everything if you use their oil. It just doesn't work that way. You can run the Amsoil to 12500 with no concerns whatsoever in the late model Northstar because even the oil life monitor tells you that for conventional oil off the shelf. Would I do that to the 502 in my 66 Chevelle...NO WAY. Amsoil says I can though. Wrong.


There are entire SAE papers written on the GM oil life monitor and one could write a book on it so it is hard to touch on all aspects of it in a single post. Hopefully we hit the high spots. Realize that a GREAT deal of time, work and energy went into developing the oil life monitor and it has received acclaim from engineering organizations, petroleum organizations, environmental groups all across the board. It is not some widget invented in a week and tacked onto the car.

The oil life monitor is not under the control of a summer intern at GM Powertrain per an earlier post....LOL Not that a summer intern wasn't compiling calibrations or doing a project on it but is under control of the lube group with a variety of engineers directly responsible that have immediate responsibility for the different engine families and engine groups. The idea that a summer intern was responsible for or handling the oil life monitor is ludicrous.....LOL LOL LOL"

_________________________________________


Thank you, Zippy!

PJ
 

·
Registered
Joined
·
13,968 Posts
where does GM say they will "Detune" the engine?

... and that long post about ZDP and the OLM system was not my writing... i quoted it in that other thread to signify that it was not my text... it was from the forums guru - a GM engineer
 

·
Registered
2007 SRX4 N*, 2004 Infinity G35 Coupe
Joined
·
2,005 Posts
Rippy...........the letter from GM which was quoted by PROF stated they will "change the calibration of the ECM, including the OLM." What he is saying I think is that is that if they were just going to reprogram the Oil Life Monitor they would have said only that.

Mentioning the ECM in the letter creates an unknown, leaves one unsure what else will be reprogrammed. Poor choice of words in the letter or......?

PJ
 

·
Registered
Joined
·
13,968 Posts
from what I have heard, the 'recalibration' is to allow the chain to stretch more before setting the SES/CEL light ... this is the first i've heard of a 'detune'
 

·
Registered
2009 SRX-4 Sport / TriCoatWhite
Joined
·
1,185 Posts
Hello Rippy;

While the letter does not specifically denote detune, it clearly states "change the calibration of the ECM... which is the "Engine Control Module" No - the letter does not give specifics on exactly what will be changed. We can only make assumptions - - actually, educated guesses... if you will.

I seriously doubt they would be tuning the engine for MORE Performance in an effort to obtain a longer life span on the chain. And leaving the current tuning settings would not accomplish a single thing. They are going through a lot of work simply to increase the oil change frequencies, when those of use who changed oil by mileage anyway, still ended up getting new chains. (I changed my oil every 5k miles despite what the OLM wanted me to do.)

and.. you may be correct as well - Expanding the "error parameters" for things like cam offset and Tension Pressure, would indeed prevent a MIL light. But that would be a very bad thing, because if the chain does go bad you no longer have an "Early Warning" system in place, the engine will continue to run causing more damage other then just a chain and guide replacement.

The proper fix, would probably have been to upgrade the guides with rollers instead of slides, additional lub injection, and lower the amount of pressure the pensioners use to keep the chain in place - - but a roller system would be much more expensive then temporary measures to extend the life out past warranty. They should also adjust the Oil Light, to display as soon as the engine is 3/4 quart low - - instead of not displaying until it is >2 quarts low.

It would be really nice if some GM Tech would get on here and share with us ,exactly what ECM parameters will be changed, and by how much.

It would be even nicer if that GM Tech was a hot girl and did it on video! :)... <~~ Just kidding of course.. well.. maybe not.
 

·
Registered
Joined
·
13,968 Posts
I'm sure you know that the ECM controls just about every aspect of the engine, not just performance/tuning so even an educated guess is still a guess - and I'm pretty sure that guessing at a 'detune' is incorrect

I think expanding the error threshold isn't necessarily as bad as you are thinking it might be... there will still be an early warning system in place

also, I don't think any tech will know what parameters are being changed... all they do is flash the module with the new calibration
(and how many of them do you think are interested enough to hack the new calibration against the original to figure out what's changed exactly)??
for free and on their own time?? not very likely...

I do agree that it would be nice if there was more information about this from GM, but guessing at what that information is and stating it as fact doesn't help

we should stick to 'what we know' and work towards expanding that

On certain 2007 model year GMC Acadia; Saturn OUTLOOK; 2007-2009 model year Cadillac CTS, SRX, STS; 2009 model year Buick Enclave; Chevrolet Traverse; GMC Acadia; and Saturn OUTLOOK vehicles equipped with a HFV6 engine, under certain driving conditions, and with extended oil change intervals, the timing chain could wear prematurely and cause the illumination of the Service Engine Soon light.
that's what we know - GM is not fixing the premature wear of the timing chain with this recalibration, they're trying to mitigate how many come in for warranty repairs that don't really need it (yet)
at least that's what I take away from this
 

·
Registered
2008 SRX
Joined
·
79 Posts
Recieved letter today but had the car in for service about a week ago and had the ECM recalibration done. Then I took it out on a trip from FL to TX (~1300 miles) and noticed ZERO performance loss and ZERO change to fuel consumption. We can all take off the tin foil hats now.

(2008 SRX w/ 26000 miles)
 

·
Registered
2010 CTS AWD Wagon 2010 BMW X5 35D 2008 GL320
Joined
·
2,623 Posts
The other thing too is that a detune would have no effect on timing chain stress, it just turns the cams and they do not get harder to turn as the power goes up. Other parts may be happy with a detune but I don't think the valve train is one of them.

The spring rate is the rate and that does not change, am I right here or am I missing something?
 

·
Registered
2008 SRX V6
Joined
·
5 Posts
Gee I got my letter today as well. Mine is a 2008 with 25k.

Since I am in a battle with the dealership over the oil consumption problem (currently 2500 miles since last oil change and already off the stick) I am interpreting the letter a little differently.
I read it that they are simply going to "adjust" the oil-minder so that it notifies the owner to get the oil changed in less miles than what it was originally designed to do. I agree with the previous poster that there was a lot of time and research in designing the algorithms for this to keep it accurate (and I'm sure a little conservative).

Now mind you we are putting $8 a quart synthetic oil that should allow us to go 7-10k miles between changes without a hitch, right?

But wait! there's a catch!

For those that wait for the oil minder, and don't regularly check their oil, you will be down 3 or more quarts, which I gather is NOT good for the internal components, including the timing change. So by shortening the number of miles between changes, they are preventing the vehicle from running low on oil, which preserves the engines internals, which they now don't have to cover under warranty.

Seems to me just a really bad CYA on Cadillac's part to cover their out of pocket on the consumption problem.

BTW, does anyone know how much oil has been consumed by the time the level hits the bottom of the stick? I have asked this question of two different dealers and the experts never seem to have an answer.

Thanks.

Great Site!
 

·
Registered
2004 SRX V6 RW
Joined
·
76 Posts
Conedoctor, you're absolutely right, the resistance of the valve springs is the only major stress for the chains. Ecm changes one way or another have no effect on timing chain stresses. One thing about the internet, it allows for instant speculation without knowing the facts.
I change oil and filter every 6 months or roughly 6000 miles with Mobil1 10/30, I'm now at 72,850 miles, usually down about a quart
at oil change time and still on the original timing chains......
 

·
Registered
2007 SRX4 N*, 2004 Infinity G35 Coupe
Joined
·
2,005 Posts
There is an oil pressure light on my 07 SRX but no low oil level "minder" or light. Am I missing something in the owners' manual, in the dash, or in the DIC somewhere?

The only way I know of that one can tell if the oil level is low is to check the dipstick.

You can have a very low oil level but still have adequate oil pressure so that the red oil pressure light on the dash does not trigger. Some have posted in this forum that their oil pressure light never came on. They only discovered they were (X) quarts low when they checked the dipstick and got no reading. Or the engine started acting up. By then the damage has probably already been done.

When oil levels get lower, it runs hotter and can actually start to foam in the oil pan.

So dropping the OLM (oil life monitor setting) from say 15,000 miles = 0% oil life remaining to say half of that in my mind only serves to get the masses to start paying attention to their dipstick and checking their oil levels regularly as prescribed in the owners' manual. And it might get those running their change intervals past the recommended time and mileage ranges back into the prescribed range.

None of this helps those who have religiously checked and changed their motor oil yet suffered premature timing chain failure. Or those who have been religious without a problem but are waiting for the other shoe to drop.

Sure, the GM notice and the service modifications described in the GM letter will cut down on "incomings" where there is no practical issue. And it may be a wake up call to owners to regularly check and change their motor oil, thereby cutting down on actual low oil related chain failures. But it doesn't address the fact that the design and function of the timing chains is actually at the core of the failure problem and hasn't been solved.

I have had just one (1) timing gear failure (not the chains) on an automobile in my lifetime, off warranty, and the engine damage was sickening (expensive)......on my dime.

PJ
 

·
Registered
Joined
·
13,968 Posts
the fact that the design and function of the timing chains is actually at the core of the failure problem and hasn't been solved.
how do we know these things for sure?

how do we know that it's a design and function problem and how do we know it hasn't been solved?
 

·
Registered
2009 SRX-4 Sport / TriCoatWhite
Joined
·
1,185 Posts
How do you know anything for sure?

How do you know you are actually reading this?

This could actually be a dream... or even a dream of a dream.

You might be dreaming that you are dreaming of reading this while you are dreaming that you in a high power job, are sitting at your desk looking at your computer, while you are actually asleep in the bathroom of your job as a janitor in the public library.

Nothing in life is for certain except death!

OK... we know a countable number of timing chains on the specific group of engines are crapping out prematurely. We know that posters have complained about V6 SRX's losing/using oil... We know that GM sent out letters wanting us to bring in our SRX's (and other cars using the same engine.) to have adjustments made to alleviate the problem. We know that GM thinks there is a correlation between driving conditions, extended oil changes, and sensors triggering the MIL. We know GM wants to make changes to extend the life of the chain.

I guess "WHY" is actually irreverent - and as long as performance and MPG remains the same or improves nobody really cares. If GM is correct - - Those of use that go by the OLM will be changing oil more often, and hopefully then extend the life of the T-Chain... and those that change by mileage, like me, will hopefully have nothing change.

Mind you :: I am a very moderate driver with my SRX... I drive my Mustang with I want to "Play". I change my oil on both cars with Mobil1, at 5kmiles. and yet I still had my timing chain replaced on my 09 SRX at 27k. So I am quite skeptical that this change is going to do much. However - - it WILL help with those that let their oil levels get too low. and low oil levels will cook a chain or guides in a hurry.

One thing for sure: This will provide great fodder for discussion going forward! :)

I wonder if I could get the dealership to loan me a 2011 CTS-V Coupe while they tinker with my SRX! (Note: the Convertible is no longer available according to www.cadillac.com.)
 

·
Registered
2007 SRX4 N*, 2004 Infinity G35 Coupe
Joined
·
2,005 Posts
Rippy..........we don't know if the timing chain issue has been solved. What we do know is that after reading the forum archives going back to around 2005-2006 and then reading forward to the current threads in this forum......the timing chain issue has persisted through six model years (2004-2009), despite (2?) timing chain changes by GM.

YET...........PROF's 09 had the timing chains swapped out at 27K, and there have been other posters with late model GenI low mileage swaps as well.

I will grant you this. Even to this day there are guys posting that they ran the motor oil level way low with the mysterious disappearing oil syndrome. Contributory to the failure rate? I think so. My friend that works at a Caddy dealer thinks so, as does my private mechanic.

Are the FirstGen Caddilac V6 timing chains particularly susceptible on a relative basis? I think Cadillac's letter confirms that.

Is a forum such as this a Mecca for those with problems? Yes.

I'm not into SRX-bashing based on an isolated number of cases in a forum. But my business mind tells me there are far too many posters over the years, those that meticulously maintained their cars, who have wound up in this predicament. And now there is the Cadillac letter.

Look, I own an SRX and have no plans on getting rid of it any time soon. I selected the V8 Northstar as a result of what I read here and on the Edmunds forum. That decision/choice cost me thousands of $ in terms of acquisition price and selection because the V6s on the pre-owned marketplace in my neck of the woods outnumbered the N* by a factor greater than 5.

I don't like anyone bashing my brand and model choice any more than you. But..........

PJ
 

·
Registered
Joined
·
13,968 Posts
Guys,
I think we're in agreement (basically) here ... I'm just concerned that people seem to be jumping to conclusions. This situation is complex, not simple and it seems that many are trying to wrap their head around this when the should just drop it and move on with more important things in life.

One thing that I'll point out is that this 'letter' GM sent out for the recall/campaign is for 2007-2009 only.... the 3.6L has been around since at least 2004 - no recall there... no recall on 2010 and 2011 either...

Cheers,
Chris
 
1 - 20 of 29 Posts
Top