Its always something with my truck. With the recent snow that we've gotten I've had to start using the 4WD and I experienced a VERY BIG problem. Every 15 seconds or so the truck will jerk to the left. It's not a drastic jerk but any sudden movement like that can spell DISASTER on the snow! I am completely stumped on this one and as I look out the window now seeing more snow coming down, I'm getting worried.

Are you driving with 4wd on bare pavement? If so, it's likely your drivetrain binding up - mechanical 4wd requires the ability to slip the wheels a bit when turning (read: not on a hard surface) because the front wheels have to turn the same number of times as the rear.

If this is occuring when you're driving straight then you might have an Auto-Hub issue. One of the hubs may not be engaging fully. (Not lubed enough, damaged cam assembly, rust inside unit).

If you have manual hubs I can send you that diagram via email.

I suggest tearing down both hub assemblies and investigating them for damage, rust and or wear. Make a point of getting a hub gasket kit prior to the tear down. It will either be an O-ring kit or paper gaskets. If the hubs check out there could be some damage in the front differential IE broken tooth on a spider gear...which is VERY unlikely but still possible if you were driving in 4WD on dry pavement for any extended time frame. (Straight line driving on dry pavement is not an issue, but excessive tight turns may cause damage in a very short distance)

Check out the attached image and if you want more detail I can forward you the complete section on Hubs. I would be inclined to think that the Fixed Cam Assembly is going to the source of your problem. While you're in there you could also see if the bearings need to be repacked.

I haven't driven it in 4WD on dry pavement but then again I've only had the truck for 5,000 miles so I don't know what the previous owner did with it. I'll take apart the hub tomorrow and see what I find.

Before you tear the hubs apart.

Were you even in 4WD when the wheel jerk occured? The way you started your concern it led me to beleive that you were.

If you were in 2WD when this happened then you may want to check the brakes first and make sure they are in good working order.

Yeah it was in 4WD. I took the hubs apart and everything looked fine. I put in new gaskets and cleaned and regreased everything and the jerk was gone. Not sure what it was that did it but it seems to be working well now. I'll repost if it happens again

If you cleaned them up and the problem is now gone perhaps there was something in the old grease that was causing the problem all this time and the cleaning/repacking took care of the issue.

I would like to hear form you in a few weeks on this issue if has been truely taken care of. If so then we can add this to the items learned file.

Almost a month strong now and no jerk. Seems like a good cleaning was all that it needed...not surprising with what I put it through. No worries here anymore even with the ice storm and 12 inches of snow expected this weekend Bring it on!

Thanks for the update J!.....Wanna hear something funny?

The same week you posted the update, I had a manual hub give the same problem. In my case I broke a spring, but a new hub and some cleaning and it was all good!