Not a good Vibe

[realfine409]

Hey Guys! Need some input on my output shaft. New Process 273 D behind my 68rfe. I have changed every u joint and hub bearings on any and all shafts since my purchase to rid the truck of a 70 mph (1800-1900 rpm) vibration. It's on the jack stands as I type this as I wanted to look for any possible thing I have overlooked. :banghead: Yup! I'm at that point. I placed the truck in Neutral, rear wheels hanging, new drive shaft (single piece) solid, u-joints tit (sic). (The new drive shaft was a result of looking for a far worse vibration when I bought the truck last year. The driveline shop showed me a slight bow, and about 9 different factory weights tacked to it. ) Shook the slip yoke, moves . 015-. 020" in all directions. The weep hole at the bottom of the tail shaft boot appears to be weeping a little. Is that enough movement to create a low frequency Buzz that you feel in your lower back through the seat. It is not present at 65 mph, and I can make it go away at 78-80 mph. I plan on doing a lot of RV'g with my 5er this summer and don't want to feel like I have to crawl or race just to keep from damaging ***** on the ends of the drive line due to constant vibration. Any input would be appreciated. In reviewing the parts book, it is not entirely clear to me if the tailshaft bearing and seals are acessable without removing the transfer case. I'm kinda hoping if needed I can R&R the bearing by removing the conical tailshaft housing.

 

[Hoefler]

I had a similar vibration in my 08. I had a vibration from 2,200-2,800 rpm. I could make it vibrate in 5th and shift it up or down and it would go away, then back to 5th and it comes back. You my try this on yours and see what your results are. My dealer chased everything from the axles to the transmission with out finding it. But I found it when it finally failed.

Here is the thread I started on it: https://www.turbodieselregister.com/forums/showthread.php?218688-Vibration

 

[realfine409]

Wow! I read your thread! In my case it's it only shows up in 6th, I'll try your method again to see if it's crank speed or shaft speed. I tend to drive the transmission as if it were a manual when not on the highway so it never lugs in those conditions, only after getting to cruising speed and setting Cruise Control. It will disappear when power comes on at slight to severe hills. That's what keeps me looking at the tail shaft slop knowing everything else is brand spanking new. I'll also check the tires again.

Thx for the thread.

 

[SierraRam]

Have you driven it with the front drive shaft removed?

 

[realfine409]

Yes, I have. Right after I bought the truck (last spring) I dead headed to CA. Felt a pretty bad vibration under my feet and in the wheel at any speed . Once in CA I removed the front shaft and a significant amount of it went away. Towed our newly aquired 5er home (5k miles round trip). Left the front shaft off until February, had new spicers installed and I re-installed the shaft. First road test still had a little 68-73 mph vibe. Looked a little closer at the front axle U-joints and saw the driver side was pretty loose. So I then replaced both sides (Spicer) as well as wheel hubs (Timkin) (I was already there why not?) Everything felt tight until we went to the outer banks. Pretty flat road all the way to the coast and felt it as soon as I got to 70mph. Played with which gear I was in and it always seem to be there while maintaining the same road speed. As I said earlier, 80+ mph is smooth as silk. The two rear tires (SRW) are not as new as the fronts and I don't believe have been balanced since I have owned the truck. I think I'll try that before tearing into the mechanical's as I've put a lot into the drive train already and still have the problem. Any thoughts?

 

[Alan Reagan]

I had the 70 mph vibe when my truck was fairly new. I put Balance Masters on all four wheels and still had some at 70 mph so I went back to Balance Masters and added the Dynamic Drive Shaft balancer. Vibration is gone. All those weights on the drive shaft are an indication that there is a problem balancing them. I tried to add the front shaft balancer but the ring wouldn't fit over the u-joints. I did rotate my shaft 180* at the rear before installing the shaft balancer and that took out a lot of the vibration. Be aware that there is some lateral movement on the rear flange when you check it. It other words, you can loosen the flange bolts where it bolts to the rear axle and actually move the shaft flange around on the axle flange. You want to make sure those are lined up.

 

[realfine409]

Good Call! I'll look at that as well. The new drive shaft is straight and true to within a few thousandths, but there are no weights on it. I'll first recheck the flange as you suggested, then look to Balance Masters. Appreciate your input.

 

[SchaeferJoe]

Hey,I also have a truck and my Truck was also giving same problem so I put my truck for servicing in truck shop and I don't know what they did but after that my truck didn't gave any problem of vibration so I think you should also give your truck for servicing

 

[realfine409]

I'm beginning to think that's my next step. I went to the Outer Banks this weekend, still has more than a slight vibe at 68 and continued until 78-80. At at a loss as to whats next. The shop was my last resort, but now if they can identify it I feel like I'll be $$$ ahead.

Thanx,