Bucking in sharp turns while in 4x4
 

Hi everyone,

I just purchased this truck (1997 F-250 XLT, older model with 8 lugs, 7.5 liter, manual transmission) and I went and got wood today and put the truck in 4x4 to do so. Everything was great and worked as it should. I then, after dropping off the wood, went to continue driving (still in 4x4) and turned the wheel sharply and started to let the clutch out from a stand still like normal and the truck started bucking. I know I was giving it enough gas and it wasn't driver error for the bucking. I went to back it up in 4x4 still with a sharp turn and it would do the same thing and then almost not let me go in reverse at all. I take it out of 4 wheel drive and the truck drives fine without and bucking. So this is telling me that It has to do with the front end at least. The ball joints and u-joints were just changed by the previous owner ( a shop did it) and I saw it on the carfax that I ran.

Anyone have any ideas what this may be? This is my first truck and I am new to this site. I tried searching but all I could find was a bucking and binding thread on a different year truck. It wasn't the same situation as mine either.

Thanks for any help in advance!

Its normal front fighting the back as the wheels attempt to turn at different speeds, you should always avoid sharp turns/maneuvering while on any hard surface while in 4wheel drive. Especially with a load in the truck, empty's bad enough good way to snap an axle.

Hate to break it to ya but yes.. it was driver error. 4WD should never be used on hard packed surfaces or clear pavement unless you're going in a straight line, when turning the front wheels have to travel further than the rear wheels and since there is no slip between front and rear when the t-case is locked binding occurs and that can lead to powertrain damage if wheel slip isn't possible.

You shouldn't be using 4x4 on a dry solid surface in most cases. What you are feeling is your wheels trying to rotate at two different speeds during a turn, and that is not good for your truck. If you are on dry ground and you are feeling that binding, that is normal - and it's also telling you that you should not be using 4x4, which is meant to be used when the "wheels can slip".

Ok, so it was driver error then! Please do no take me as ignorant. I'm still leaning. Thank you guys for responding to this! :-X22

Since this thread is pretty much useless, I guess it should be deleted.

Also, ujoints do not allow constant rpm at an angle like a cv joint does.
The more angle you put in the ujoint, the stub shaft does not turn the same speed as the inner shaft... Sounds weird huh. But that's the biggest reason why the front bucks and pulls around the corner when turned sharp. Normally the differential can take up the difference being that the inside front tire turns less than the outside front tire, but then you get the rear pushing the front through the corner because the rear travels less than the front.
Anyway, you don't use 4x4 unless it's needed, you don't use it on ground where the tires can't slip, and you try not to use it at full lock.

Or, use more throttle, with spinning tires you won't notice the bucking.

Thank you for all the good information! I will not use the 4x4 unless I really need it! Thanks for saving me possibly a huge headache down the road! :-X04

I forgot to say the stub shaft oscillates at a different speed as the inner.
Driveshafts have two ujoints at same angle will cancel out the oscillation.
Here is a great description of what I mean with math and everything

Universal joint - Wikipedia, the free encyclopedia

nope, not ignorant.
just learning how to do things the proper way.

and don't worry, we all make silly mistakes now and then.
life is a learning lesson.
the day you stop learning now things is the day you get put in the ground.

That is a great representation on how it works. Thanks again! And thanks tjc transport for making me feel a bit less dumb! Glad to be on here! Seems like a great community! :-X03

+1, well stated.

i am 57 and have been driving very large trucks for 44 years..(yes, i started driving tractor trailers at 13 years old)
i have homer moments all the time. just today i was not paying attention and forgot to step on the clutch coming to a red light and could not figure out why the truck was fighting the brakes. http://i41.photobucket.com/albums/e2...lies/doh-1.gif