Hey everyone,

My truck has been vibrating, and now worse in certain RPM ranges, get off gas goes away immediately, tire been rotated around and no difference,
My bud is pretty sharp and while in the truck he seemed to think it's the rear diff going or drive shaft maybe lost weight's or bad U joint's.

Trucks got 158,000, no real towing really, while Ive owned it for 4 years.
And when bought looked barely ever worked.
Would just replacing the two rear shafts be worth it?

Anyone know someone here in area of Ohare I could trust to look at it and tell me?

john

 

The rear end is pretty robust, but your roads are harsh on the exposed parts of the undercarriage in the winter. Without seeing the truck, my default suspicion is the driveline... particularly after the problems I've had with mine.

 

Been combing threads for some time and see sometimes may just be an issue with greasing the splines.

 

I have had your symptoms on two different trucks. Both times, it was the U-joint on the rear drive shaft.

 

If it was me, I'd take it to a driveline shop, let them replace the ujoints, carrier bearing and balance/paint it to where it's like a new one...pretty cheap for the work done.

 

i was in the same situation, bud. ...(wind thru a pipe sound). After 2yrs, of dealing with it, when my throw out bearing went last month, i decided to pull apart the D.S. and replace the rearend. Well, cant say for certain, but can say, one if not both, WAS the source of the noise...no grease in the driveshaft and/or the rearend was beyond help, and a "better" used one, was installed in its place....no more "howling" sound, which was pedal sensative...let off, no noise, on pedal, noise..up to 2k rpm.

 

With a bad u-joint, which I've had plenty of from snowplowing, I've always gotten a little clunk when you go to take off from a stop sign or light. Not huge, but just a little clunk as the slop in the u joint gets taken up. On this last one I replaced 2 weeks ago, there was a little clunk and a high pitched chirp on take off. A noise could definitely be a symptom of a bad u joint. Even if that's not it, they're about $25 and take about 45 minutes to change. If you're trying to save a few bucks, you can usually test by
1.) park on level ground
2.) truck in neutral, wheels firmly chocked
3.) climb under, grab the driveshaft, and see how much rotational play is in it before the tail shaft out of the rear end stops it. If it's a u joint, this will usually show you.
Just be SURE the truck is chocked well. I was loading something in my dump truck with a skid steer, and left it in gear. While loading, the truck popped out of gear, and I became a track star trying to catch it as it rolled towards a ditch. Just glad my 2 boys obeyed and stayed in the garage while all this happened.

 

Back again,

I would just like to say thanks for all the responses with knowledge and experience.

Ive decided because working on the truck here as apposed to my place, that Im going to a local driveline place. He threw me a good price to replace all rear Ujoints, Carrier & rebalance the shafts, with my miles? what the hell.

I appreciate the advice to tackle it myself and read some great threads on this subject with these 2 great links,
Slip joint regreasing
2004 F250 Slip Yoke Service

Sorry cant find the threads, to give exact names, but again thanks to all who posted here and everywhere else I read. You guys here have saved my butt bigtime when I had to do a bad bearing and replace my waterpump here in the driveway (Thank God again for the 2 warm days outta no-where!) and right down to simple stuff like fuel filters.

So with that I spent 20 bucks and joined, What a fantastic Site, Cheers!
john

 

Hello again,

Conclusion! I took it to the somewhat local place, I appreciated their work and honesty.

Anyway, first off the most rear Ujoint on the shaft was shot, move it easily by hand, shame on me for letting it get that far, I also as the one member had said would get the clunk if I let off the gas fast. Tell tail sign there right?
Other source of problem, the Center Bearing, Spun by hand like a roulette wheel he said, which would be the noise I would hear, like a spinning metal sound.

He described the wind through tube to me before looking at it, and said that sound will travel as though its under you. However it didnt sound that way, and the Bearing being shot confirmed it. The Tech/mechanic said before swapping it, that he thought perhaps there was rear diff noise when turning the truck, but thankfully it was gone when all was finished. And of course the bolts on the carrier were stripped, so he took care of that.

Drove home and feels as though it sails nicely again, well as good as a Super Duty can sail I suppose!
Thanks for all the help! Cheers Brothers & FTE!
Hey how long does it take for my membership to appear?

john

 

Thanks for checking back in. We sometimes forget to 'close the loop'.