Engine/Transmission (1994 - 1998) Help Please, truck is bucking like a bronco!!!

[doodad]

I seem to be having a strange problem with my truck. I am not even sure which forum to post it in,LOL.



A couple of months ago a trnny line wore through where it was rubbing on the bell housing. The leak was caught quickly and the transmission only miss shifted once. I had it towed to a shop where it was fixed. They also added rubber hosing to protect the lines from rubbing. Well about two weeks ago, I noticed that when doing approx 60-70 MPH and you go over a bump while not applying the pedal very much, sorta coasting that the truck starts to buck like crazy. If I keep it at the same speed it just gets worse and worse, till I either have to let off the pedal or hammer down on the pedal. Both of those make it go away. I checked the track bar and steering stuff everything seems good. I have a new steer box/pump/lines and a DSS bar. Any help would be greatly appreciated. I am HOPING to god that my transmission is not giving up on me. Thanxs in advance Doodad

 

[doodad]

I just did a search and read TSB 18-29-97A. and some other posts about this. The problems described are exactly what is happening to me. whenever I hit a slight bump or lightly decellerate it starts bucking like a wild woman Oo. .



Why does this TSB state for manual transmissions only? Mine is an Auto and it is doing what it says to a TEE. I have already had the throttle linkage recall done about three years ago. My truck is bone stock, no engine or transmission mods yet.

 

[doodad]

TTT Someone out there must know something...

 

[Andy Redmond]

Add another (2nd) throttle linkage return spring or a more heavy duty one that you source on your own. . let us know how you like it. .

 

[Dbonzi]

death wobble

Do a search for death wobble and you'll find all kinds of info

Good luck!!!

Haven't had that expirence yet but understand its kind of scarey.

Dennis

 

[Andy Redmond]

I don't think its the death wobble or caster shimmy, worn track bar can cause this to be worse.



Check into the spring we discussed and add another (it goes from the bottom center of the injection pump back to the speed lever on the back of the injection pump.



Andy

 

[tp0d]

Sounds like its a TC lockup problem. Try driving that speed over a bump with the brake light switch unplugged. If that switch is on the edge of adjustment, a bump can cause the TC to unlock and cause the bucking problem. Could also be a dirty TPS, get some contact cleaner and hose it out. I removed mine to clean it, and mand did it make a difference. do a search for " TPS AND CLEAN" on the boards, without the 'and' it wont let you search.





good luck



-jerry

 

[BRayls]

what have you found? if you have the transmission apart let me know I can send you that v-b.

 

[JoshPeters]

I had a problem like what you are having. Check your transmission mount. I've seen quite a few of them bad. Mine seperated all the way through letting the tail of the transmission and T-case jump up and down causing the truck to buck. Let off or step all the way in and it would go away.



Josh

 

[BNH4221]

Doodad,



Shot in the dark but how about your TPS? Maybe try a squirt of cleaner in it just for kicks? Can't hurt and might even make it better!

Good luck!



Steve

98 QC 12v

168000 happy miles

 

[viper700]

I picked up a new 04. 5 3500 DRW 4WD a few weeks ago in Kellogg ID. and headed north to Anchorage, Alaska where I live. I had this bucking problem 5 times on the way home. It seemed to happen coming over the top of a hill about 65 mph, I can't remember if cruise control was in each time this happened or not? This has not happened since. Could this be related to cruise control and a change in fuel requirement due to peaking the climb and the fuel control to hiccup or what ever. I am very new to Diesel.