Carrier bushing from the pics looks cracked and bad to me. Yea grabbing it while your on your back it might seem "tight" but going 60mph and having the dribeshaft spinning like 10,000rpm is a completely different all together. For all the money you spent on just replacing parts go spend another 60 and buy a new carrier bushing and two ujoints and finish the rear driveshaft

 

Also the ujoints are the same way they might look ok and not have play but they are most likely extremely dry inside and they make all kinds of noises when they get this way

 

Bad ball joints will wipe out new hubs pretty fast. That very well could be why you are getting that grinding noise.

 

Did you only have the rear portion of the driveshaft balanced? When i inquired about getting my driveshaft rebalanced (also a two piece) at a local driveline shop with excellent reputation, i was told he needed both pieces to balance it.

Also, flat blocks are what you should have. I have flat blocks in my CCLB and almost down to 0 vibrations...hoping new carrier bearing and balancing takes care of it. Only reg cabs and super cab short beds should have tapered blocks.

 

Yeah, I've had u-joints that felt good, both installed and with the driveshaft off the truck, but were bad and causing a vibration [and they also felt good to my dad, who was a mechanic for 40 years]. Once they were removed from the driveshaft, bone dry inside.

 

Thanks guys for the input! I completely understand what you guys are saying, and have been thinking the same thing. The only thing is that I'm thinking I'm going to go to a custom one-piece driveshaft come summer time once I do the lift. So I don't want to put any more money into the two piece driveshaft unless I have to. The vibration doesn't bother me too much, but that whining noise scares me. I don't want to mess up that new rear end! So do you guys think I would be ok until summer, or should I just get the whole driveshaft balanced together and get a new carrier bearing? I've already got a new u-joint for the front part of the driveshaft, just didn't put it in because we didn't take it out. Or is there any vote against the one piece driveshaft?



Yeah it could be. I should be replacing them soon, but may hold since I was planning to do the lift and rebuild most of the suspension in the summer time.



Yup, I only had the rear portion of the driveshaft balanced. Obviously I should have had the whole thing done. You would think my driveline shop should know that. Seems like they may be part of the problem.


Thanks for the confirmation on the blocks! I was pretty sure that's how it was from all the reading that I did, but just wanted to make sure.


So how you been Miles? Haven't talked to you in a while. I haven't been very active on here lately. How's the truck running? Ever get that "ghost" pedal figured out? Still liking the lift?

 

I put a Skyjacker 6" all-spring lift on my 1997 F250 super-cab 4X4 and ended up with a low frequency rear end vibration when put under power (take-off & acceleration). The first thing I did was buy and install the "Skyjacker" D/S carrier bearing spacer as I was told by Skyjacker. It was a waste of money and only got worse. I read up a lot on this subject all over the internet including here, and there are dozens of theories that I didn't think made sense. I have built and lifted several older 4X4's but this is my first with a carrier bearing on the rear D/S. I learned a long time ago that you must put forth every effort to keep your input and output pinions on a parallel plane to prevent oscillating tendencies of the D/S loads. Rule of thumb is no more than 15* angle at U-joints and no more than 1.5* deviation from pinion(s) parallelism. These rules are for daily drivers up to about 8" of lift and the BIG trucks run under different needs and rules.


Having said all of that, I got under my truck and studied hard. I reached up and grabbed my D/S at the carrier bearing and shook it hard. The bearing moved about 1/2" in the rubber isolation damper in the carrier and I knew what was going on (oscillating tendencies of the D/S loads). I turned the tapered shims around on my rear springs 180* which matched up the pinion parallelism and went to my local machine shop and had them build me a one piece driveline with slip joint, bolted it on and Shazam! Smooth as silk from stop to 90 mph, even under loads. The down side is expense. $680.00 which included a D/S balance. Worth every penny of it and I recommend it if you have a lift with a two piece D/S.