2004-2007 Cadillac CTS-V Performance Mods Discussion, Tremec Transmission Freshened @ 172K in Cadillac CTS-V Series Forum - 2004 - 2007; Can tell the car is getting close to 200K miles.
Had the transmission pop out of 2nd and 4th gears ...
Had the transmission pop out of 2nd and 4th gears after a gear change a couple times. Wrote it off as laziness in not "planting" them. Then a couple weeks later the tranny popped 6th gear when cruise control was pushin up a hill. Started happening with more frequency until after another couple weeks 6th became unusable.
Called the guys at RPM Transmissions on a Friday. They did a Stage V rebuild and a LS7 package on the unit @ 100K when replacing a locked reverse gear. Drove the V up to their shop on a Tuesday, three weeks ago.
Planned on killing three days working from the hotel while they worked on it. Took it to the shop at 9 on Wednesday. Asked the guys if they could run me back and they asked, "Why? We'll be done with it after lunch.". I'm like "Yea. Right." but I decided to hang around. (These guys have an amazing array of corvettes, camaroes and GTO's in the shop at ALL times. NA, turboed, blown, juiced. You name it they work on it.)
Well the tranny was out and we were lookin at the damage before lunch. Sixth gear was almost smooth and it had damaged the main shaft and a fork (I think). Guess all those miles luggin around in 6th had finally taken their toll.
My bud says, "No problem. We've got the gear in stock and lookey here!" as he reaches into a bucket full of Tremec parts and pulls out a brand new main shaft left over from a recent custom job. "We're golden." We left to eat lunch.
I walked back out into the shop around 2:30 and they were moving the transmission back under the car to reinstall. Done by 3:30. DAUM! ($1700 incl parts/labor)
As an after thought (foretelling impending doom), earlier in the day I asked the guys up front to service the rear end while it was up in the air. This is the original rear that was rebuilt under warranty back at 40K. The mechanics didn't get the message until the were practically finished with reinstalling the trans. He pulled the plug to go ahead and drain it while he finished up front. And, you know it! The magnetic plug looks like a porcupine with all the shavings and pieces of springs sticking to it. The rear end innards are toast.
Well what we gonna do now? It gotta come out, so they finish the transission install and the rear end is on the table opened up before closing. The owner comes out to take a look and sure enough the housing's full of shrapnel, all the clutches are badly worn and there is only one spring left intact. Pretty hard to believe GM would intentionally buy/use junk like this.
Then the owner says, "Wait a sec. I think we've got something covered in dust back here that'll work.". He comes outta the darkest corner of the parts room with a box marked CTS-V 3.42 Open and sure enough it's a brand new rear end for a project that some customer had abandoned a coule years ago. So the owner offers to take the new housing, the 3.42's (I've been wanting these for a while) and my posi and put them together with some corvette clutch packs and custom springs thay have made for themselves. Then he also offers to take my old housing and use the open rear with my 3.73's and their special parts and build me a spare "for emergencies". How much? $500 bucks. SOLD!!!!
The rears were rebuilt, the new rear end installed and they picked me up in the car before lunch Thursday.
I can not say enough about RPM Transmissions. Besides being a well oiled organization (and just total GM gearheads) they are also just plain good folks. Everyone of them. If you EVER have transmission questions or need some work done I'd strongly recommend you give them a call.
Off now to see what happens when I try to do new engine mounts.......
They have solid billet keys made to their specs, micro-polish all internal, some tricks they've learned running turboned and blown corvettes at the tracks over the years. If there's an equivalent vette part, they're exchanged. They didn't have to do the polish as this was the second time around. The gains are being able to drive with confidence that you ain't gonna hurt anything anytime soon and everything in combination with Luke's shifter bushings on my custom shifter means a REALLY tight, accurate (might as well be gated) assembly. We didn't change any gear ratios or anything like that. The biggest performance gain the first time around was doing the LS7 flywheel and clutch kit. The difference in engine spool was incredible.
LOL, I'm just wearing whole gear assemblies out making miles on the J.O.B.
There is a slight increase in transmission "note" in the cabin. But then, I REALLY like the "note". Not so bad you need to adjust stereo volume or anything like that.
I've always run 3.42 in my horsepower cars. Gives the power adders something to work without strainin the rev limiter. As a matter of fact, I asked RPM's owner what he was running in his 9 second vette......yep, 3.42's. Every car in RPM's stable runs 3.42's. I find that, in practice, I don't really see better mileage unless I'm makin one of my 16 hour runs up from Tallahassee thru Indianapolis. What happens after driving with the 3.73's for so long before getting around to this change is having to "relearn" all my shift points. The 3.42's let 1st gear do a little more than just get the car rolling. That's good for 60' times. Now I tend to run the RPM's up a little higher than I used to between gear changes (gonna start calling it L.P. for lugging paranoia) and then on the short daily runs 20 miles on a four lane, 62 MPH max. state highway to and from the office usually ends up being done in 5th @ 2100 RPM. 6th runs roundabout 1800 RPM.
Note: I belive I've proven that lugging gears around town at low RPM's and then running them at a continuous 2,200 RPM for 4 hour intervals, three or four times a day, WILL wear transmission parts much faster than carefully beating on them.
I would believe and it seems logical that the combination of the V's sixth gear and the 3.42's could potentially increase top end slightly. I haven't taken him out for a top end run since the work has been done. But then I'm not an expert on this so if someone with more knowledge than me would care to share their thoughts?
A stock V, (with any computer related limitations tuned out) can usually max out 5th, but not advance (increase mph) in 6th due to aerodynamics, horespower, and the high gear ratio.
Whether a modified V can benefit, in terms of top speed, from a switch to a 3.42 rear gear presumably depends on whether the amount of added horsepower can take advantage of the higher 5th gear ratio (174 vs 160) that results.
Gene, what happened to you happened to me. My '04V had about 160k miles when it started getting real difficult to put in reverse. Then one day in 6th gear with the cruise on, the bottom dropped out. Had it towed to the shop and the main shaft and 5th/6th gear were gone...and I had been putting it in 6th every time I got above about 40 mph. So yeah, the T56 doesn't like to be lugged. I went with a Keisler Engineering rebuilt T56 out of a 2005 LS2 and a LS7 kit from Scoggins Dickey. Keisler upgrades the synchros, etc., and everything's cool except the slight vibration I get at 1800 rpm. Not enough to shake the steering wheel, but you can feel it in the seat of your pants.
Darkman, I may have figured out what it is. A few days ago in another post, you put out a Cadillac document about possible sources of vibration. One of the causes listed was loose exhaust pipes. Another post from a guy said he had his tranny worked on and when he got it back, the car was "louder". All this has been going through my mind, because when I got my car back after this tranny transplant, the car was louder, I could smell gas, and I had the vibration. I now think that since the exhaust pipes have been off several times to do work and the car has high mileage (meaning the exhaust pipe packing has been hot so long it no longer seals), and I can smell gas on start-up (make that exhaust gas fumes from the area of the shift console), then I have an exhaust leak that could also be causing the slight vibration I feel! The spent gases could reach a velocity at 1800 rpm where they start cascading out the pipes, causing the vibration. Under 1800 rpm, not fast enough to bother, over 1800 rpm, so fast they go out the pipes and don't leak (as much). What do you think? I'll be checking this after the holidays, and will report back.