: How to Instructions - Differential Lube Change



StealthV
07-24-04, 07:32 PM
Changed the differential lube today on my V @ 2165 miles. Here's the process to do-it-yourself!

1. Items Required:

-- Two quarts of GM #12378261 GM Synthetic Axle Lubricant SAE 75W-90 (~$27/quart)
-- One 4 oz. bottle of GM #1052358 Limited Slip Axle Lubricant Additive
-- One 10-mm hex allen wrench
-- Suction gun
-- Oil drain pan
-- Set of Rhino ramps or equivalent
-- Creeper to roll under car
-- Troublelight to see in the dark :coolgleam
-- One CTS-V (most important part!)

http://www.nitro-nights.com/2005v/getrag/vdifflubechange01.jpg

2. Before the oil change, drive at least 10-15 miles at highway speeds to warm the differential.

While working under the car, the engine, transmission, differential and exhaust will be extremely hot. Be careful, safety first!

3. With the rear of the V safely supported, remove the fill plug first. The fill plug is located on the driver's side of the differential, half-way up the side of the differential housing and is a bit tricky to get at with the exhaust pipe in the way. Try using both ends of the 10-mm allen wrench to loosen the fill plug.

http://www.nitro-nights.com/2005v/getrag/vdifflubechange02.jpg

4. Position the oil drain pan under the differential and remove the drain plug with the 10-mm allen wrench.

Caution! Hot lubricant will come out quickly!

http://www.nitro-nights.com/2005v/getrag/vdifflubechange03.jpg
http://www.nitro-nights.com/2005v/getrag/vdifflubechange04.jpg

5. While the differential housing is draining, clean up the drain plug. Here's the "before" shot of my plug. The dark glob on the end of the magnetic plug is the metallic paste that has formed from normal bevel pinion gear break-in.

http://www.nitro-nights.com/2005v/getrag/vdifflubechange05.jpg
http://www.nitro-nights.com/2005v/getrag/vdifflubechange06.jpg

6. After the lube is done draining, install the clean magnetic drain plug and tighten snugly with the 10-mm allen wrench.

http://www.nitro-nights.com/2005v/getrag/vdifflubechange03.jpg

7. Remove the top of the suction gun and fill it half full with the new GM diff lube. Pour in the bottle of limited slip additive and then continue to fill the suction gun body with diff lube until near the top of the gun. Place the top of the suction gun back on, go under the V, place the hose in the fill hole and press in the handle on the suction gun to push the fluid into the diff housing.

8. Once the suction gun is empty, refill with diff lube and continue to fill the differential housing until lubricant begins to spill out of the hole.

9. Reinstall the fill plug and tighten until snug.

http://www.nitro-nights.com/2005v/getrag/vdifflubechange07.jpg

10. Clean up your mess, safely lower the V and take it for a spin and enjoy the knowledge that for not much money, you've done your differential a favor! :worship: V

(Yes Reed, you can put it on the FAQ) :cheers:

Rich H
07-24-04, 08:37 PM
Excellent pictoral write-up Stealth V. Belongs in a Manufacturer's O&M manual.

I have a question on the "metallic paste" on the magnetic drain plug. You say this is "metallic paste that has formed from normal bevel pinion gear break-in". This material looks identical to that found on my engine oil drain plug. I just changed the engine oil again today (2600 miles) and it had nearly the same amount of this material on the plug as it had at the first change (700 miles). It appears to be much too fine to be caught by the oil pump screen but should be collected by the filter. However, it seems to keep showing up on the plug.

Is it possible that this metal paste is a result of machining of gear or engine components and is not completely flushed out during, or prior to, assembly? In any case, this is compelling evidence that the rear differential fluid should be changed before the manufacturer's recommendation (Caddy says never if not in servere service).

StealthV
07-24-04, 09:14 PM
From my experience, a LSx engine takes 10,000 and sometimes more to fully break-in. If your drain plug has the pasty slime, without any visible metallic slivers, it sounds perfectly normal for 2,600 miles. The drain plug will begin to be noticeably cleaner each time you change oil.

Dreamin
07-25-04, 01:44 AM
:worship: Excellent writeup!! What do you use to add those cool arrows??

One small request... Step 3, BOLD, highlight, somehow emphasize the "remove the fill plug on the driver's side" statement, maybe add a "Do This First"... If Joe-do-it-yourselfer removes drain plug first, and then for whatever reason cant get the fill-plug out... they're F***ed.

StealthV
07-25-04, 01:56 AM
Thanks for the input Dreamin, I wordsmithed and added some bold lettering. :cheers:

wildwhl
07-25-04, 01:57 AM
Dreamin

I 2nd this request - good point.

StealthV
07-25-04, 12:50 PM
Is it possible that this metal paste is a result of machining of gear or engine components and is not completely flushed out during, or prior to, assembly? In any case, this is compelling evidence that the rear differential fluid should be changed before the manufacturer's recommendation (Caddy says never if not in servere service).

It is highly unlikely that the contaminants on the magnetic plug were from the machining or assembly process, but the result of the gears all getting "happy" with each other.

The company I work for builds hundreds of pieces of off-highway equipment each day and we take contamination very seriously. Parts are rejected anywhere in the machining or assembly process if there is even the smallest about of chips, dirt, foreign debris, etc. The reason we do this today is in the past we learned that not following this process led to high early-hour, "infant mortality" of components in our machines.

Since I don't work for GM, I can't comment on their processes, but I'd wager they take it very serious as well by properly cleaning all the parts as they move through the manufacturing and assembly processes. The few seconds it takes to clean a part during the build of the car is incredibly more cost effective than fixing someone's car under warranty because it was built "dirty."

Rich H
07-25-04, 09:36 PM
StealthV - I can't comment on GM assembly & machining practices either but contamination happens to even the best assembly plants. I have read on the BMW boards that there was a problem with a small sampling of M3 engines that suffered premature failure due to this very problem - leaving machining residue in the engine.

Since this metallic paste is present in so many GM components including engines and rear differentials, I would tend to agree with you that it is a break-in byproduct and not a QA problem. However, there are some people on this board who have not seen it on their engine drain plugs after the first oil change. I think you are one of the few who noted it on the differential drain plug. But then, very few have reported that they have changed it yet on the V. Based upon your input I think I will wait until ~5,000 miles and change both my rear differential and tranny with synthetic lubricant. Before I saw your writeup I was going to follow the manufacturer's recommendation and not change either.

By the way I see you have a K&N oil filter (HP2006 long) installed. That's what I installed at my last oil change. It took between 5 and 10 seconds to fill it with oil at startup. I was a little worried when the dash and nav screen flashed "low oil pres - shut down engine". I guess this is normal with an oversize filter.

StealthV
07-25-04, 09:48 PM
Fill the engine oil filter with oil before you put it on the car. You can put about 3/4 of a quart in a HP-2006 filter. Guess I need to write up a engine oil change how-to procedure. :)

Rich H
07-25-04, 10:46 PM
Good advice for this application - although you can't do this with every oil filter since many (most I've dealt with) are installed horizontally.

tzoid
08-01-04, 10:07 PM
real, big time racers will tell you, quite loudly(!) to NEVER pre fill an engine oil filter before installing. You will then be pumping unfiltered oil (even tho it's new, it very likely could have contaminants in it) thru your engine. Most of them have a kill switch on the fuel system or the ignition system to allow for turning over the engine without firing to build up oil pressure...unless your running a very special, highly modified engine, I wouldn't worry about the low oil pressure when you change oil and first start up. Fact is, you really don't need anything more than the stock oil filter...most users change the oil and filter WAY before they need too. We're all fanatics with the baby!

StealthV
08-01-04, 10:37 PM
If fresh M1 has contaminents big enough to get caught by the filter it is pretty crappy oil and poor quality control. Been filling my filters with oil since 1984 and yes, a racer taught me that trick. :cheers:

rabid
10-14-04, 07:08 PM
For those that have done this, how much fluid did the diff take to get to the right level?

I ask because mine only took 1.4 bottles today. (1 bottle being 946ml)

SlvrVee
10-14-04, 07:28 PM
Mine also only took 1 1/4 bottles and I was pretty worried. I am hoping that someone knows for sure.

StealthV
10-14-04, 07:56 PM
Yes, that's the proper amount. If you filled it up and it is oozing out the fill hole, you are golden. :thumbsup:

rabid
10-14-04, 08:34 PM
Thanks!!

BeagleBrains
10-14-04, 11:04 PM
real, big time racers will tell you, quite loudly(!) to NEVER pre fill an engine oil filter before installing. You will then be pumping unfiltered oil (even tho it's new, it very likely could have contaminants in it) thru your engine. Most of them have a kill switch on the fuel system or the ignition system to allow for turning over the engine without firing to build up oil pressure...unless your running a very special, highly modified engine, I wouldn't worry about the low oil pressure when you change oil and first start up. Fact is, you really don't need anything more than the stock oil filter...most users change the oil and filter WAY before they need too. We're all fanatics with the baby!
I use a replacable cartridge type oil filter that filters at about 8 microns. To this I have installed a bleadoff line to a 2 micron filter (which is too restrictive for maintaining normal oil flow and pressure). Amsoil has such as set-up available, also. This is ten times finer filtration that any "standard" filter. I prefill the canister to ensure that pressurized oil reaches the oil gallies and bearings as quickly as possible. 90% of engine wear is suffered during initial engine startup because the bearings are dry until oil flow at pressure refills the oil passages.

StealthV
10-14-04, 11:09 PM
Stephen, are you using the Amsoil cartridge filter? If so, I've looked at that one in the catalog and have a little curiousity in trying one out. Which model number is for the V?

TheTwins
10-15-04, 01:55 PM
Good info, nice job w/the write-up. Q - just curious why is the stock exhaust back on your car?

benjet
10-15-04, 02:00 PM
Good info, nice job w/the write-up. Q - just curious why is the stock exhaust back on your car?

I *think* (and I know I'm assuming and posting for Stealth - I know he can post for himself) if you look at the date of the original post, no aftermarket exhausts were released at that time. Therefore not back on, but not yet off.

TheTwins
10-15-04, 02:03 PM
My bad, you're right. Thought those bending / holding marks on the exhaust pipes looked a little suspicious that's all.

BeagleBrains
10-15-04, 08:40 PM
Stephen, are you using the Amsoil cartridge filter? If so, I've looked at that one in the catalog and have a little curiousity in trying one out. Which model number is for the V?
The filter I use is a Nascar racing design. I will get the info tomorrow.

BeagleBrains
10-17-04, 01:07 PM
Engine Oil Filters. I have used Canton/Mecca Oil Filters for many years. They are very expensive for the initial set-up. One must buy a filter housing first; either spin-on or remote installation. From then on, just buy the their universal 8 micron filter media for about $13.50 each. Bulk purchases are a little less but quite an outlay when buying 24 at a time. The approximately standard 4-1/4" replacement housing is $95.00 which gets you a machined aluminum unit. A remote filter housing is $102.50 to which you must add the engine block adapter plus hoses, etc. The CM Site provides vehicle specific application information; or, if no auto/engine specific applications, there is a cross-reference to major a manufacturer index such as FRAM. They provide the thread type and O-Ring size information for any car to verify the correct application. Cadillac CTS V LS6 CM Housing = 25-232
Note that the housing length is added to by the bottom plate and attachment set screws. I had a 6-1/4" on a Pontiac Trans-Am and managed to scrap it off in a rough poorly maintained parking lot. The aluminum failed the scrape test and did not affect the engine block. I like the larger unit for the much increased filter volume. High flow with no pressure drop.
www.cmfilters.com/

Dreamin
10-17-04, 01:30 PM
I have used Canton oil filters and their oil temp thermostat's on previous cars... *extremely* high quality product. :thumbsup: