Engine/Transmission (1994 - 1998) Does your manual transmission truck 'buck' in reverse?

[HoleshotHolset]

My '98 does...



What causes it? Seems like the clutch is slipping, then sticking rapidly...



Should I worry?



Since the truck in question is a '98 12-valve - I thought this was the appropriate forum. However, this isn't just a 12-valve/NV-4500 issue... it could happen to any generation truck with a manual transmission... . or even your neighbor's K-car.



Should we have a forum where EVERYONE would see issues related to all generations of Cummins/Dodge trucks? Very seldom do owners of one generation look in the other generation's forums...



Matt

 

[Gary - K7GLD]

Matt, I think what you describe is not unusual - and CAN get pretty obnoxious when trying to back a load uphill. My '02 had a slight tendency to do that with the stock clutch - and does it a bit more with the new Cerametallic clutch, not at all unexpected.



The long 2-piece driveshaft, combined with any rear axle wrap-up will cause a tendency for uneven drivetrain loading that can cause the clutch engagement to become erratic as it's load seemingly varies due to drivetrain fluctuations.



About all that can be done with a stock drivetrain and suspension, is to keep all components tight as possible and in good repair - the looser it gets, the worse the chatter can be. Otherwise, anything that can be installed to reduce or eliminate drivetrain "rubber band" effect will make a big difference.



My '91 with an automatic displayed a noticeable vibration as I took off from a dead stop - all that went away when I had a US Gear OD unit installed, which involved conversion to a 1-piece driveshaft...

 

[drrhoades]

I try to keep the rpm's up when trying to back up slow so that the bucking doesnt happen. With the trailer I just put it into 4 low and back up. If I have to go around tight I slip it back into 2 wheel until I get it straightened out. Seems to work for now until I get a 2 low kit. I get the bucking in 1st to if I am trying to go slow. I think that the axle wrap is a big part of it and also the heavy duty clutch.

 

[NBowlin]

mine does the same thing. do you guys think that traction bars would solve it?

 

[HoleshotHolset]

Excellent comments - thank you.



I'm not opposed to traction bars as a possible solution to reduce the bucking... they'll be necessary down the road when I hook it to a 'seemingly immovable object'. :-laf



Matt

 

[TPCDrafting]

We just had a SBC Con OFE put in about a month ago. I drove it on a 500 mile trip, backing up a couple times on flat ground with the GN horse trailer. No problems going either direction. A week ago my wife took the truck/trailer to haul some horses and came back mad because it was bucking off the line, sticky to shift and bucked pretty bad backing up the trailer. I'm not sure what the problem was other than she doesn't drive a stick too often anymore. I do use 4-low to back up hill with the trailer or when I am in a tight spot and wanna go extra slow backing up on any grade. We're thinking of a 2-low kit, but do want to be able to back up in 2wd in a hurry when needed without having to pull levers throw switches and cross fingers.

 

[JGheen]

That's a weird dilemma you guys are experiencing. I have been through three clutches and none gave me any "bucking" of any kind in reverse. Even when I used to tow my 16K fifth wheel it never bucked when backing the trailer in somehwhere. I have recently installed some custom traction bars to help with my extreme axle wrap I was getting, but even with the major wrap i was getting, I never had an issue. Hope you get it figured out.

 

[drrhoades]

The bucking seems to occur more when the truck is empty. The more weight on it the less the bucking happens.

 

[BV]

Both my old 92 and the ole mans 92 do it. If you can get the clutch all the way out (fully engaged) and back up real fast you got it made other wise 2 wheel low range works wonderfully or raise the idle and slip the clutch.

 

[y-knot]

For me, most of the time that Bucking in reverse is caused from the spring wraping up and unwraping. To rid that I have always find that Traction Bars work. I have some installed on both my Ford and Dodge, the install is quick and painless, while the cost is not much at all. I also had a Chevy that bucked bad when backing up a loaded trailer, a good set of traction bars fixed that one also.



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As you can see here I run the Rancho traction bars with a custom rear bracket.