Vibration and noise at rear of 85???

[wmflyfisher]

I have about 6 inches of total suspension and no body lift in the rear of my pickup. I am assuming that the rear chunk is aligned right with the TC. the TC flange is parrallel to the diff flange at rest. At about 40 I get a vibration when coasting in gear with no foot on or just barely on the gas. Also, I get what sounds like a bearing noise, kind of raspy, at every speed with the same amount of gas, none or just barely. I even hear the noise when I press the clutch in also. Any sugestions, its about to drive me nuts!!!

[DontStall Rockcrwl]

i have the same sounding problem you have. when i give it full on gas i dont hear it but when i give it a little or no gas i hear a bearing type noise. and when i cruise in neutral or push the clutch in. thought it was my 3rd but its not. any help would be appreciated

[derek]

sounds like gear float. when you have a lot of lift and the driveline angle is steep it will make a grumble/rattle noise in your t-case/tranny when you let off the gas.
mine has done it for the last 4 years or so.
dont think it hurts anything, but it gets annoying.
most have cured it by running a c-v in the rear.
if you already have a c-v then it it probably another problem.
check u-joints, pinion nut, flange nut on t-case.

derek

[Bob Garrett]

I had the same type of noise from the front shaft on my 80 series (full-time 4WD) after installing a 5" lift. New u-joints helped for a while, but the vibration came back after a while. Replaced the shaft with one that had a cv on one end and no more noise or vibration.

Bob

[BigMike]

Replaced the shaft with one that had a cv on one end and no more noise or vibration.

We recommend CV joints on the rear drive lines on any Truck (short and long beds) with dual cases and more than approx 4.5" lift.

[Hyena]

Well, that could explain my vibrations too, but they have gotten better over the past few months.

[DontStall Rockcrwl]

well sounds like im going to go with the CV. i talked to a buddy of mine today and said he knew someone with the same problem. so they did the CV joint in rear thing and he didnt know why they did it. now i know. thanks guys

[CRSHROX]

Im dealing with the same issue / Vibe . Im definitely going with a CV in the rear. It solved the similar problem I had with my 91 Blazer w/ 8 inches of lift. I have a question though .
Do you have to use a CV from a straight axle front shaft ? I have heard that an IFS CV will work without clearancing ? Any truth to that ?

[rockhound]

Im dealing with the same issue / Vibe . Im definitely going with a CV in the rear. It solved the similar problem I had with my 91 Blazer w/ 8 inches of lift. I have a question though .
Do you have to use a CV from a straight axle front shaft ? I have heard that an IFS CV will work without clearancing ? Any truth to that ?

I want a CV rear driveline too. I'm going to use the one from the front shaft of my '85. Hey Joe, clocking my rear diff helped a lot with the horrendous vibration I had at 65-70 mph.

Sorry 'bout jackng your thread. wmflyfisher.

the Hootman complains of the same malady after a 4 inch lift on his '95 Runner.

[CRSHROX]

 its all good Al !    the majority have said the same thing ...clocking the rear. the only other thing that im scratching my head about  is that i had very -very  little vibe before i did the 5.29s , now its pretty bad especially 65-70. my only though is that its because everything is spinning so much faster now that any little vibe i had before is now magnified x 10