Took my truck back to the dealership for a squeak in the tranny. I thought it might have been the throwout bearing as it seemed to change with the positions of the clutch. Dealer now says that it is something internal in the tranny and they are going to tear it apart friday and see what they find. The truck only has 5800 miles and already getting stuff rebuilt. Anybody else seen failures in the POS zf 6 speed?http://www.dieselplace.com/forum/smileys/Angry.gif

Mine's still perfect at 43k miles.

Bet it's your flywheel.

I've not had any problems with either one of ours. One with 47K and one with 20K. http://dieselplace.com/forum/smileys/Cool.gif Edited by: camp

As of today I've got 70,411 miles and 1812.6 hours on my 2001. I've never had a problem with the clutch or transmission. I did have the pedal assembly replaced for the warm weather creaking noise (eventually came back).

Have had the same noise on my 2003 2500 HD the dealership had to replace the flywheel at 10K noise is gone but now I have a hyd. problem with the clutch master cylinder and t/o bearing

Have had the same noise on my 2003 2500 HD the dealership had to replace the flywheel at 10K noise is gone but now I have a hyd. problem with the clutch master cylinder and t/o bearing





My tranny squeaks when I put just a little pressure on the clutch and then as I depress it all the way. The tranny has to be warm for it to make the noise. I drove about 200 miles straight the other day and it would squeak even when the clutch was out. I guess I better call the dealership and have them check the flywheel before they tear the tranny apart.

Just got off the phone with the dealer and they are putting a new t/o bearing in. I'll be glad to have her back.

I've got 6000 miles on my truck and I'm having the second flywheel and the tranny rebuilt on Monday. Mine squeaks like crazy with the clutch in or out. But that the weakness on these trucks and it sucks.http://www.dieselplace.com/forum/smileys/Disapprove.gif

These trannys do seem pretty weak. I have seen a lot of post about low mile rebuilds and flywheel problems. I guess I probably need to sell the quad so I can keep my flywheel in one piece. I was debating putting a aftermarket clutch in it, but I don't think the rest of the tranny can handle the power. I bought the 6 speed so I could mod it more without spending big money on a tranny. Guess I was wrong.

From everything that I've heard up until now, the tranny is strong but the clutch/flywheel are weak. I'm interested to hear why the Jraed83's tranny is getting rebuilt, what was the failure and how did it occur?

The flywheel is a definate weak link but that is it. The tranny is very tough. About the only way to tear one up is to run it low on oil or change gears way to aggressively. The clutch can start slipping with increased power after time but it does hold fairly well for a stock clutch.

Somewhere I read, which I can't seem to find right now, that someone from the board was making 1 piece flywheels. Anybody now who that was?

I am in the process of getting them made.

CPMac


Where are you having them made and what is the cost going to be. Haven't gotten my truck yet but I want to have everything lined up for when I decide to go crazy.

CPMac,


With the one piece flywheels, is there any concern over the engine harmonic issue at the 300-400rpm range potentially tearing the teeth off gears in the tranny? I seem to recall an earlier thread discussion about why they (GM, F$rd, etc) have the dual-mass flywheels on diesels in the first place and if I recall correctly it had to with some uncontrollable diesel engine harmonic at low rpm (300-400rpm) which could potentially destroy the tranny. I could be mistaken. I can't find the thread at the monent.


I would love to replace the dual-mass flywheel with a one-piecer that would hold up and not have to replace the dual-mass one every 16-20K miles. Please let me know if this becomes a reality since I would like to have the option to replace with a real flywheel.


Do you know of anyone making an aftermarket heavy-duty clutch setup yet? It's quite obvious the stock clutch is pretty wimpy.


I also recall reading something about changing out the hydraulic (brake) fluid in our clutch systems with something else (DOT3 vs DOT4 or something like that ?) because apparently the heat buildup from the throw-out to the slave cylinder causes the fluid to boil which causes the "hard" (extra travel) clutch condition after long runs in high gear.


Thanks,


Tim

As of today I've got 70,411 miles and 1812.6 hours on my 2001. I've never had a problem with the clutch or transmission. I did have the pedal assembly replaced for the warm weather creaking noise (eventually came back).


How do you know you have that many hours on your toy? Is there some computer that tells you?

Several companies are involved in helping make these flywheel and clutch kits. I don't have a finished product so I can't quote a price but they aren't going to be cheap unfortunately.


The trans does rattle a lot at an idle with a solid flywheel and a solid clutch disc but it is mostly a noise issue. I am getting sprung hub discs to help with that but it is almost impossible to get one made to handle diesel tq.


The only mod you can do to the factory flywheel and clutch is to replace the disc with a better one. That will hold more power but shortens the life of the flywheel.


The hours can be found on 01-02 trucks by the trip reset with the key off I believe.

The tranny is pretty tough. Forders are using this same tranny for quite a few years now. SuperF350 has done numerous pulls with his, and only replaced clutches/flywheels, if I remember correctly.


Over at the dieselstop.com, there have been posts about imput shafts being worn down. Only a rare few, and heavy haulers at that.


Re the squeak from the pedal: Mine does it at 65* and warmer. Its pretty annoying...

I got the truck back and no squeak. Love the mannual but hate the clutch flywheel problems. Someone needs to make a good flywheel that can be tested for the low rpm tranny noise and a good heavy single disc for driveability. Maybe somedayhttp://www.dieselplace.com/forum/smileys/Cry.gif

Someone needs to make a good flywheel that can be tested for the low rpm tranny noise


If you want tranny noise ride in my truck. I had an aluminum shift handle made so I can use a Hurst T handle. The only problem is the factory shifter has a rubber isolater. All the tranny noise now comes into the cab through the shifter. The nice part about not having the rubber is I can feel the gears better. I can really hit the 1st to 2nd shift now.

Re the squeak from the pedal: Mine does it at 65* and warmer. Its pretty annoying...





I have the same problem. Pedal replaced and hydro cyl, twice! Now the tech reps are denying change out until new tech bulitin with real correction to problem. This came from my dealer's service manager yesterday.





BTW, they have parts on order now to replace my t/o bearing and "flexplate". I have just over 37K on mine.

Sorry I've been away for a while but the tech said that they came out with an updated flywheel that they put back in mine. It seems to have a bigger balancer on it and hopefully bigger springs. As for as the tranny goes GM would let them replace the tranny because they wanted to make sure it wasn't the flywheel. But its still has the vibration in 5th. I have yet to know what caused it.http://www.dieselplace.com/forum/smileys/Disapprove.gif

. . . .


I also recall reading something about changing out the hydraulic (brake) fluid in our clutch systems with something else (DOT3 vs DOT4 or something like that ?) because apparently the heat buildup from the throw-out to the slave cylinder causes the fluid to boil which causes the "hard" (extra travel) clutch condition after long runs in high gear.


Thanks,


Tim








Has anyone else read anything similar to this? I have a very HARD clutch pedal after strong acceleration. The clutch slips visciously when I use the juice. In stock mode it does not slip and the pedal does not get hard. I don't know how to deal with the dealer on this issue as they will not be able to replicate the problem.http://www.dieselplace.com/forum/smileys/Ermm.gif


Any ideas?

I am in the process of getting them made.





CPMac;


How is your flywheel design coming? Anymore info?


Thanks,

Deadeye the clutch slipping is what causes the hard pedal in your situation and therefore the dealer won't or can't fix that. I should have an aftermarket clutch setup in a month hopefully.

CPMac,


Can't wait for your setup. Sounds very promising.


One thing I have noticed that doesn't really make a whole lot of sense to me (maybe it's obvious and I just don't get it, which is likely :-) is that if it is in fact the clutch slipping, then how come it only happens in 5th and 6th gears and not the lower gears?


I have had this very noticeable "vibration" sound around 2000+ in 5th, now I get it in 6th, and it keeps getting worse and worse on hard accelerations. W/o a box, I can't make it happen. Fire up the Quad-110 and bam, it's there under hard accels especially uphill or towing. I am hoping it's either the clutch or flywheel and not the tranny or tranny input shaft.


Why wouldn't the clutch slip in 2nd-4th and make the same noise?


Tim


Thanks,


Tim

It takes more to turn the input shaft in higher gears so eventually if slipped enough it will start slipping in lower gears.

Tim;


I have the EXACT same problem u do cept: mine will slip in 3rd or 4th if I am hitting the pedal HARD. Over time it will get worse.


No notice of vibe noise but will start paying attent. Pls describe the how the noise sounds?


Thanks.

Deadeye, what level are you running on the Hot Juice? I've put a few days worth of playing on the 90hp level and have never had any slippage.

Camstyn;


I was using lvl 5 loboost 5. Now at lvl3 loboost 3. Still slips when I hit the pedal hard, even in 3rd or 4th. I can here the engine rev but the speed increases slowly when slipping. Interesting that the OEM Tachometer does not respond nearly as quickly as the digital tach on the attitudehttp://www.dieselplace.com/forum/smileys/Confused.gif.


CPMac;


When you get the new clutch ready I will be interested. However, I thought it was a flywheel you were working on? Have you examined the new OEM flexplate (IIRC you were the one who posted the new part number - my receipt shows p/n 12582861) to see if it is significantly improved?


Thanks,

Deadeye,


The sound is like something grinding, almost like a bearing. The vibration is not a lot, but it's there, kinda like bearing noise... :-(


If it's the clutch, I'm not worried, I own the repair anyway. If it's the flywheel, I'm not worried, 100K warranty. If it's the tranny, or input shaft, THEN I'm worried, since I am at 35,983 miles. Truck has been in my garage (i.e. parked) all week thinking about this. Dealership is 11 miles away. I already had it in there a month ago, w/o the box, couldn't make it happen. I have tried and tried, been running w/o the box for the last couple weeks, running the crap out of it, no noise/vibration anywhere. What gives?


Tim

Ive heard that 5th gear is straight through. Engine to wheels directly.


Mine does it too when Ive got a load in the back. 2200-2700 rpm under acceleration...


I dont know why a box would do it...Good luck

Tim;


I am going on a long drive this weekend. I will do some driving w/ the box set at factory and then at diff lvls and loboost. I will pay attention to the vibe and noise. Will let you know what happens. For now, I cannot get the problem to pop up at factory settings, either.


My guess is that what you are noticing is related to slippage of the clutch. Mine did the hard pedal this morn when I passed a car again. Lo-boost and lvl at 3. I have noticed the vibe in the clutch pedal when depressed but not all the way feels like a rotation at speed with a grind but no noise. Except, this am noticed some ticking or clicking, very slight down near the pedal inside the cab. Not continuous or regular. May have been related to bounces and not clutch at all.


CPMac;


Do you know of anyone who has a diagram of the pedal through clutch/flexplate system which could be posted? I think it would help me understand things a lot better.


Thanks,


John

Your transmission should have the same warranty as the duramax, 5yrs/100k, no? I'm pretty sure the complete drivetrain is included.

Only the engine (power plant) not the entire drive traain are under the that warranty. Mine is beyond the b to b. But the clutch was an issue prior to the b to b runnout so I can still push to get it fixed. Problem is the dealer cannot fix it if GM doesn't have better parts. Also, without a box they will not be able to duplicate the problem!http://www.dieselplace.com/forum/smileys/Evil Smile.gif

Camstyn,


Only the engine is 100K. :-( Drivetrain is 36K. Any wear item (i.e. clutch) is not covered except for "unusual wear".


Still would sure like to know for sure what the noise/vibration is I get. While I think it's the clutch slipping, I am not convinced of it. I seldom get the hard pedal after the noise, I usually only get the hard pedal after hour(s) of highway driving, although I have seen a hard pedal after the noise w/o hours of highway driving, but it's the exception rather than the norm with mine.


Thanks,


Tim

The ole 6 speed is going back in the shop. This clutch is a joke. I hope they get this truck fixed this time. T/O bearing lasted 400 miles before it started squeaking again and now it is worse than before.

I did a two long drives this weekend 2.5 hours each way, flat land. few stops. 65mph mostly. Below freezing. Box set at factory. No clutch slippage or hard pedal. However, the clutch pedal started squeaking like a pig again as the cab warmed up . . .


BTW, with the new 35" tires I got over 26mpg on the way out! On the way back I only got about 15mpg! I think there must have been a mistake in the odo # I used but cant figure it out. Not possible the clutch could have slipped that much with no hard pedalhttp://www.dieselplace.com/forum/smileys/Clown.gif.


Anyhow, this morn I set the box back to LvL 3 LoBoost to 3 and the clutch slipped in 5th gear and the pedal went rock hard after a not so hard accel. I am taking it in to the dealer on Wed. http://www.dieselplace.com/forum/smileys/Cry.gif


PS they are going to charge me $50 to 100 to reflash my ECM for the larger tires!! http://www.dieselplace.com/forum/smileys/Angry.gif Any local member that can do this for free (or a lot less)?


I doubt the dealer will be able to help me with this because they will not be able to recreate the problem. I will likely have to look to CPMac or some similar 'inventor' to get around this problem. I wonder what the labor will cost to pull out the tranny once I get aftermarket flywheel, pp, and clutch, etc??

Dealer called said they were ordering a new flywheel. It is the new part number which is supposed to be better. Any one run the new flywheel with a hp box. Just wondering if it holds tq any better than the old one.

Gray Max;


My new flexplate is only 3 weeks old. Has not fallen apart but the clutch will not hold squat. I don't know what the problem is and I don't think the dealer does either. Going in on Wed. Will let you know what they determine.


Regards,

Bolts didn't come in for the new flywheel so my truck sits for another day. Deadeye was your clutch slipping before the new flexplate?? I never did slip mine but I did make the flexplate growl several times. I am starting to wonder why I stay with GM. My old 8.1 had cold start knock like crazy. My 95 350 had nooooo power and now my dmax is in the shop more than it runs. To boot I got spanked by a 03 cummins saturday. I was stock but still sucks to get beat. We need a super HD clutch and flywheel for these trucks. CP help!!!!!!!

Gray Max;


Actually, No. I do not recall any slippage prior to the new flexplate. http://www.dieselplace.com/forum/smileys/Ermm.gif