For starters, I have read several threads about driveline vibrations, etc... and I do not "think" I have an issue with my driveshaft, but If I was positive, I would not be posting on this message board, so all opinions are welcome.... I am listening.

I have a (1999) Disco II and overall it runs and drives great.

I recently "2 months ago" replaced my front driveshaft with a NEW one and it has been driving great. I still have the old one, not sure if I will keep or sell.

Here is the problem:
I live about 60 miles from Dallas and it's all highway. Yesterday, when driving at speeds higher than 40 MPH, I noticed a very slight vibration. If I took my foot off the accelerator and let the vehicle start slowing down, the vibration would stop every time.

--> When I started accelerating again, the vibration would not start up immediately, it would take 20-30 seconds, etc...

--> If I just kept driving it at a constant speed (70MPH), the vibration would come and go, with about 60% of the time with the vibration and 40% of the time perfectly normal.

--> Another Test: With the vehicle driving at 70 MPH...once it starts vibrating, if I carefully shift the tranny into Neutral, it has no effect on the vibration.

Is this vibration more likely to be a wheel bearing or suspension bushing ?
What is the best way to determine ?

 

How many miles on your truck, how often do you grease your 7 grease fittings, have you checked the roto flex for cracking and where did you buy the replacement shaft.
Have you tried ruling out the front shaft by removing it and engaging your CDL and are you leaking any gear oil from either flange on the t/case?

 

It has 143k miles

I bought the (Heavy Duty Front Drive Shaft) on E-Bay, but through BPUTAH.
It has 5 grease points...Claims to be balanced.

I have NOT checked the roto flex for cracks, but I will.

Since I just bought the rover a few months ago, I have not (personally) greased the 7 grease fittings myself, but I immediately took it to my local lube shop when I bought it. Even though I like the guys at this shop, I'll probably never take back there again, because these guys looked clueless.
I have my own 3 bay garage with lift, so I'll probably be doing this in the future.

I have no "apparent" leaks from the Transfer Case, but I'll inspect closer.

I could easily remove the front drive shaft to test, but I'm not sure about the CDL you are talking about.
One typo---I have a 99 Disco II, not a 2000.

Thanks for your reply.

 

if you have no in cabin selector for cdl it can manually be engaged via nipple on transfer case

for info search "center differential lock"

 

Hi
I had until recently mystery vibrations so rebuilt the front and rear propshafts all with new UJ's and rotoflex coupling. I noted the old rotoflex had cracks in the rubber although on the vehicle these weren't visible. Having taken the D2 for a few hundred miles drive since now I must say the vibrations seem to have disappeared so have the metallic clunks between overrun and accelerating. Although the old UJ's and cardan appeared OK with no apparent slack when rebuilt they were noticeably tighter. In my humble opinion it was the old worn rotoflex (120K miles on it) that was causing the main problems. I guess vibrations can emanate from so many different things from wheel balance and bearings, transmission wear defects (bearings etc) and steering *****, suspension bushes shock absorbers etc which makes it difficult to eliminate the causes unless one replaces everything systematically which is very time consuming and costly and that assumes it finally cures these mystery vibrations. Good luck