jerking at low speed

[ScottLewis]

When I pulled into our campground and drove slowly looking for our site, the truck began jerking. Again this AM while slowly leaving camp the jerking resumed. I could actually see the transfer case shifter moving with the jerks. No service lights came on and once above 15 MPH seemed ok.

Any idea of the cause/problem?

 

[Crunch]

No service lights came on and once above 15 MPH seemed ok.

Did you also check for codes?

 

[ScottLewis]

No, I just assumed there wouldn't be any without CEL coming on.

 

[ScottLewis]

No codes.

 

[RVTRKN]

Were you turning a tight turn, and in 4 wheel drive?

 

[seafish]

Were you turning a tight turn, and in 4 wheel drive?

Good question!!!!

 

[ScottLewis]

No turn, not in 4 wheel drive. Straight pull, like hundreds before. This felt quite different. I had transmission and transfer case serviced by the dealer about 750 miles ago. Trans fluids looks/smells good and up to full mark. It was pretty hot at over 92* and followed a 100 mile hilly tow when it first happened. I've never experienced that much movement of the T Case shift lever before. Could a bad TPS cause something so dramatic and yet still drive fine going a bit faster?

 

[seafish]

perhaps your trucks 4wd engagement is acting up ... i.e. neither fully engaging or disengaging.

also possible that a front axle shaft u joint or wheel bearing is going bad.

 

[AH64ID]

Can you recreate it again?

1 or 2 piece driveshaft?

 

[ScottLewis]

1 piece shaft. It happened again yesterday when I took the truck in to have AC serviced. I left the truck with the shop overnight to investigate. I did suspect a 4wd problem but had not used 4wd for quite some time and have a manual shift 4wd.

I appreciate every bit of suggestion I can get. We're just a few days into a month or so travel to Texas and beyond so I am concerned about getting stranded somewhere. We're near Cottonwood, AZ now and I do have a reputable shop working on it but, so far, they haven't isolated the problem. I'll make sure they inspect u joints and transfer case

 

[AEdelheit]

My 04.5 did the same thing, all the drive-lines had been gone through and never did find the problem, did it on and off for 50k miles, curious what you find!

 

[ScottLewis]

Can you recreate it again?

1 or 2 piece driveshaft?

I note you referenced lube for the Carden joint back in '12. Do you think failure of the joint might be the issue?

 

[AH64ID]

I note you referenced lube for the Carden joint back in '12. Do you think failure of the joint might be the issue?

If you haven't been lubing that joint it could be the issue.

My brother never lubed his 06 and around 150K miles it starting making occasional noises and vibrations.

 

[ScottLewis]

If you haven't been lubing that joint it could be the issue.

My brother never lubed his 06 and around 150K miles it starting making occasional noises and vibrations.

Lubing could certainly be an issue. Although I usually have the dealer service the truck, on more than one occasion I've had to point out the lube point to the "professional" tech. And when I've greased it myself, I've had some doubt whether the grease actually made it into the joint. The shop owner said he would inspect the joint and front shaft but hasn't gotten back to me yet.

 

[Wayne M.]

Usually a bad joint will reveal itself at hi speed with a “buzz” or walking speed with a squeak-squeak.

 

[Ozymandias]

When I pulled into our campground and drove slowly looking for our site, the truck began jerking. Again this AM while slowly leaving camp the jerking resumed. I could actually see the transfer case shifter moving with the jerks. No service lights came on and once above 15 MPH seemed ok.

Any idea of the cause/problem?

So does mine with a cold engine, driving slower then walking speed with a feathered throttle.
Out of a camp site is the perfect spot for it. Then it bucks, but on mine it is clear the engine does it, the driveline just shows the torque waves. Slightly more throttle or zero then it stops immediately.
It seems like the ECM has some trouble to decide about fueling at such low loads.

I don't care about it.

 

[Prairie Dog]

The front Ujoints can cause a similar condition. If you turn the wheel and drive slowly, the steering will oscillate back and forth by itself if they're bad.

 

[ScottLewis]

Usually a bad joint will reveal itself at hi speed with a “buzz” or walking speed with a squeak-squeak.

That echos what I had on a Ford Bronco years ago when Cardan Joint went out, esp. the squeak-squeak.

 

[ScottLewis]

The shop owner said they went over the front axle, u-joints etc. carefully. Said everything was tight and they couldn't determine any problems. He certainly could have started throwing parts at it but said he didn't believe in that practice. He is replacing my AC compressor and other recommended parts so at least we'll be cool on the road.

Thanks to all who responded. I guess when my stay here is over, I'll just proceed with my trip and hope for the best.

 

[EDankievitch]

My 05 with the manual transmission had developed a bucking when coasting down hill. It ended up being a cracked injector. The one injector would over fuel that cylinder causing the engine to speed up more than the computer was asking for and it would respond by cutting back the fuel. If I ran the engine at a fast idle out of gear (neutral ) you could feel the surging/ bucking in the engine. It drove me nuts until I tried my friends Smarty tuner and turned up the power a wee bit. the extra fuel made the failed injector nozzle way worse to the point that I had to replace the set. When I removed the nozzle the crack was quite apparent until the unit cooled off then it closed right up. I went with Dynomite Diesel for new injectors the engine had never ran so smooth after the new units were installed.