I have stock 03 F250 CC with 135k miles. I have a vibration only when I start from a dead stop and then the vibration goes away once the truck is at 15 + mph. It feels like it is coming from the drive shaft. The truck does not off road any its mainly highway/pulling usage. Could this be a U-joint, carrier bearing, or something else problem? Any input would be great and any pics on how to remove a U-joint/drive shaft would be greatly appreciated.
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Thanks

 

Can you describe the vibration? Does it feel like the shaft is vibrating? Or is it a series of 2-3 "clunks" that feels like there's slop in the line? If it's the clunks, then it's probably your slip yoke needing some grease. The 2 piece drive shaft connects between the carrier bearing and the rear differential and has a tendency to push the grease out of the splines (not that Ford put much in there anyway). I have to re-grease my slip yoke about every year or so. Check out these links for the clunks:

https://www.ford-trucks.com/forums/8...aking-off.html
https://www.ford-trucks.com/forums/8...t-splines.html

If it's more of a vibration I would check the carrier bearing bracket to make sure it's torqued correctly and make sure it's properly shimmed. If you notice that the vibration is only when you're loaded or unloaded it could be a driveline angle problem, but you can't rule out an out of balance shaft either.

 

https://www.ford-trucks.com/forums/8...placement.html

Here is a link to a thread that I was involved in dealing with removing a u-joint. Posts number 12 and 13 are the important ones if you are removing the driveshaft and any u-joint. If you think it needs to be balanced, (the driveshaft) you must remove the entire driveshaft, including the carrier bearing and take it to a driveline shop. It doesn't cost much to have this done. If it were me and I removed the driveline, I'd have everything replaced that moves. That way you won't have to mess with it again for many years. Obviously this is also a good time to re-grease the slip yolk too.

 

Here is my best way to describe; it feels like a mild case of wheel hop when you are doing a burn out. Thanks for the reply.

 

Does it have a manual or automatic tranny?

 

If you have an auto tranny, it sounds exactly like what mine was doing. It was only when starting from a complete stop (if I was still rolling it wouldn't do it). Grease the slip yoke and you should solve your problem...

 

1. Auto

2. That is exactly was is going on. It only happens from a complete stop and it does not happen any other time.

Thanks

 

My truck does the exact same thing. I will grease the slip and see what turns out.

I read in another thread that it could be a bad injector??? I am not experienced enough to comment on this though...


Andy.

 

I'd do the greasing first. If you already have the grease it's free and takes an hour in the driveway. If not, it costs $5 for a tube of grease. It's worth a try before jumping to injectors...

I thought my tranny was on the way out (or my driveshaft was shot). An hour later it was like a new truck...

 

Mine had similar symptoms and it turned out to be the limited slip was worn out. Don't ask me why, but it had a shimmy from a dead stop, even going in a straight line. Someone on this site explained why, but I can't remember....anyway, I pulled the rear end apart, replaced the limitless slip with a locker and have never felt it again. I inspected the old posi and the plates were nearly bare. It was definitly worn out. Just another possibility.

Jim

 

Mine does the same thing. It seems to happen when turning a corner going very slow (around 5 mph). It is a rumble / vibration. After you pick up speed, you do not notice it at all.

I had my slip joing re-lubed as well and it seem to help but I still have the issue now and then. I had a mechanic tell me that is was my clutch in the limited slip rear end. He said his Dodge does the same thing.

 

You can get a rebuild kit for those LS rears. I think they are about $100 or so.

 

You might need to add some friction modifier. When I swapped my rear fluid out it was recommended (on here and by the dealership) that I not add any friction modifier to start with. If I felt/heard rear end chatter that I should add a couple of ounces at a time until it went away. Granted you don't have a new truck, but you never know.

 

I changed the rear dif. oil 6 months ago with Mobile 1 syn. However the problem was there before this and the syn oil did not fix the problem. The motor runs great so I'm sure it has to be coming from the drive shaft/or u-joints. Thanks for the input I'm going to do a re-grease on the drive shaft. It just amazing how little things like air pressure and grease can do wonders on how your truck drives.

 

think you'll find the problem is either u-joint or carrier bearing