Grind/Grab feeling on take-off (getrag)

[JGrefenstette]

philip, and all others for that matter..... i replaced all three rear drive shaft u-joints and the carrier bearing. i still have the launch shudder. it has gotten a little less aggresive, but its still there. do you suggest stilll adding spacers to the new carrier bearing?

 

[Philip]

Yes I would try the spacers. It was a TSB from Dodge about a launch shudder. I'll go threw my TSB book and find the number.



Here is a link to the TSB Dodge released on launch vibration shudder.



TSB 03-02-93



Here is a pretty complete lis of the TSB's covering our trucks.



1989 - 1993 Ram TSB index

 

[1stgen4evr]

With any repair, do one thing at the time and after a trial run, you either have fixed it or must move to the next possible solution. The simple point being, don't do two things at once as you won't know what actually fixed the problem.



So now it is better but not cured. Still without actually driving the truck, it may be that you only need to perfect you clutch let off technique. My straight drive 93 has a half million miles (original clutch) and has since soon after new, had a slight shudder from the release. I have derived a happy medium of let off that is somewhere between instant dumping of the clutch and slip start (using the clutch as a dry torque converter).



If you only have 1/4 inch of shim, try doubling that. But you might also try some let off technique changes.



Again, good luck and I am confident that you will solve the problem as you learn the art of diagnosis and repair.



James

 

[dpuckett]

I have to agree with James about diagnostics being an art form.



When letting off the clutch, do you give it any fuel? If so, it needs to be VERY little- just enough to keep it from dying. These things are designed (though not always used as such) to be engaged, THEN fuel added, kinda like a big rig. If you have trouble with 2nd, try starting in 1st for a while til you get the hang of it. And it is also possible you're already doing it correctly.



DP

 

[JGrefenstette]

well this is interesting. i was used to driving my parents cars before i got the truck, and with those little forign cars, you have to really slip the clutch to keep it from dying. with the dodge, i dont give it any fuel, just ease the clutch out in 2nd... and it pulls right along. one good hills starting out, it can go from idle, but it makes it a little smoother and lest chugging if i help it just a little. ive tried many different techniques mostly because im still getting used to how the clutch and the the engine feel, but im fairly convinced its not my left foot causing the grind/nock, my dad was the first to notice it the day we got it. ive felt it when my brother drove it too. i think unfortunaly its somthing more involved than adjusting my foot. :-laf



thanks for the ideas, i really appreciate them. im all ears to every one of yalls comments and sugestions.



jimmy

 

[RedRamAndy]

Hello Jimmy,

My idea on this isn't a simple one unfortunately. I had a rattling problem with my Getrag equipped D250 and decided to pull the trans. It turned out to be a bad clutch disc. Now I also had the grind noise that you mention. It would grind while Iwas letting the clutch out to start off in 2nd. When the pedal was on the floor, no noise. When the pedal was all the way out, no noise. It only did it as the clutch started to grip. Well, while I had my trans out, I looked at the pilot bushing. It was the original bronze bushing, very dry and very worn. It was almost worn through the sides. It was a heavy 1/8" bigger than the pilot stub. I put a new bronze bushing in with very little high temp grease when I put it all back together. I was tempted to go with the newer needle bearing pilots, but did not want to throw any more $ at a used clutch than I had too. By the time this bronze one wears out, I'll probably be putting in a whole new system anyway. If you do go all new, consider the roller bearing pilots. The OEM one was a whole 5 bux. Fit my budget nicely.

Watch that heavy trans, get a trans jack. My 800lb Harbor Freight unit served me well. You'd want the bigger jack to pull a trans/transfer case combo.

Good Luck

 

[JGrefenstette]

thats exactly what i was afraid of. i tried some difrernt tecniques for letting the clutch out, more throttle more feathering, a number of different approches, and it actually has quited down with more throttle. i guess my not chugging it as much i dont let that bearing take its sweet rough time getting in. hopefully it will last me another few years. my thought is, that if i have to get into the clutch or trans, ill just spend the 2,000 for the nv4500 replacement kit after the core charge it do it right. i dont really trust the getrag after talking to enough people that have had issues.

 

[RWWinslow]

When I had my Getrag in the truck and your symptoms, it was always the front pilot bearing and or front cluster bearing assembly - hopefully, for your sake, I am wrong. I was able to nurse it along for several thousand mileas of highway driving on one occasion - it seemed like the start and stop of town driving made it much worse.



Good Luck

 

[dpuckett]

Look in the 2nd Gen forums- the 4500s have enough of their own issues, namely 5th gear coming off, and the Liquid Gold oil to fill it with ($50/gal is cheap).



The ONLY issues I can think of to cause anyone any problems are 1) lack of lubrication (Dodge manual writers are to blame, as they dont recommend fluid changes of the Getrag),

2) bad driving habits. You have to roll into the throttle with this or any truck transmission, and maybe

3) improper factory setup, though they usually failed fairly quick, and this most likely wouldnt apply to your transmission.



Daniel

 

[JBenzinger]

James,



Next time you are under your truck look at the transmission mounts. Sounds kind of weird, but bear with me here... On the transmission cross member there are two rubber mounts. At the center of these mounts is a piece of steel tubing. As the rubber gets old and soft, the transmission will come closer and closer to resting on the steel tubing. Any heavy turn or hard acceleration would push the transmission down in the steel tube which would not dampen any of the vibration.



I used to get a BAD vibration/noise in my truck under load and I thought my U-joints were bad. When I was under my truck I noticed that these mounts were falling apart so I decided to change them. This fixed the problem and the truck runs much smoother.



You may try checking this out, it is fairly inexpensive.



Has anyone else run in to this? Let me know what you find.



John

 

[RWWinslow]

I made the same repair about two years ago - it helped.

 

[JGrefenstette]

the trannny mounts is a really interesting idea. ill definatly check that. unfortunatly the more i drive it the more im becoming convinced that its the pilot bearing. it also feels like its getting worse.



if it is the pilot bearing that is bad, how long do i have till its undrivable or really really bad??



how hard would it be to replace this myself, and how expensive.



i was pulling out into traffic this afternoon, and was on a hill at a right turn. i tryed giving it a little throttle like i have been because that has been smoothing it out. but when i started out, it was the worst ive felt yet. i mean it was really not good. smoked a lot and shudderd way more than i was comfortable with. i can live with a little shudder like i have been, but that was not healthy.



also, in revese untill i completly let off the clutch pedal, it surges/bucks real bad.

 

[JBournes]

Well I think you are talking about the same shutter and grind i was having. Mine would get worse if i drove the truck a while. If it was the first time i drove it for the day it was fine. But if i drove for any period of time and stopped and started again it was back. It was worse when i would try to turn from a stop. Well mine was the rearend had it rebuilt for 1300 bucks. I dont have a posi anymore because when they called to get parts for it there gear guy said the dana 70 was bad about the posi and its real hard to even come by the parts. Plus he said this way would last longer if all this was true. Anyway i would start with your rearend of the truck just my 2 cents.

 

[JGrefenstette]

well that is real good to know. if i check the rear diff. fluid, would i see any signs of it being bad (metal shavings, real dirty and/or old fluid?)???? is it possible to have the rear end checked by a shop for realativly cheap?



also, how did you determine it was the rear end and not the clutch?



did rebuilding the rearend totally solve the problem?



when i try to start with my wheels turned at all it make the problem much worse. if i give it just a little throttle and feather the clutch a bit i can start it pretty smooth, unless im on a steep grade or tight turn. but from a dead stop on flat ground it will shudder when i let the clutch out unless i feather the throttle/clutch.



how safe is it to drive the truck in this condition????

am i ok to keep driving it?

 

[Leper]

I am a noob to these trucks, but I have had a similar issue on my 4x4. You may want to have someone drive the truck while you stand outside of it and look at the way the tires move. Pay close attention to the front ones. Look for any back and forth movement. Any worn front rubber bushing can cause movement of the front axle. I have seen worn spring eye bushings cause the axle to move on its horizontal axis and cause a problem like you are describing. It also caused the truck to pull at random to one side or the other while applying the brakes.

Just another idea.

 

[JGrefenstette]

well, this problem has been present with the stock tires, then was still there, if not a little worse, after i put on 33"-34" BFG a/t's.



good thought though

 

[JGrefenstette]

well that is real good to know. if i check the rear diff. fluid, would i see any signs of it being bad (metal shavings, real dirty and/or old fluid?)???? is it possible to have the rear end checked by a shop for realativly cheap?



also, how did you determine it was the rear end and not the clutch?



did rebuilding the rearend totally solve the problem?



when i try to start with my wheels turned at all it make the problem much worse. if i give it just a little throttle and feather the clutch a bit i can start it pretty smooth, unless im on a steep grade or tight turn. but from a dead stop on flat ground it will shudder when i let the clutch out unless i feather the throttle/clutch.



how safe is it to drive the truck in this condition????

am i ok to keep driving it?

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