<!--quoteo(post=1524442:date=16 Jun 2009, 06:26:name=kiwimike)-->QUOTE(kiwimike @ 16 Jun 2009, 06:26)
<{POST_SNAPBACK}><!--quotec-->Hei
Sorry I do not type Norwegian well enough to communicate this problem [img]style_emoticons/<#EMO_DIR#>/rolleyes2.gif[/img]
would like some help diaognosing a strange noise I am hearing occasionally from I beleive the rear Diff.Of a 1991 Chev Suburban 2500 Diesel.
The noise sounds like a fast Sewing Machine,or like you are dragging a "ratchet strap",this is accompanied by on or two "thump's" (like the rear differential is locking) then its all back to normal.
I changed the rear diff fluid and filled it incorrectly with a normal 80 W90,I changed to 80W 90,half a gallon about, that was for limited slip diffs but the noise still occurs sporadically.Whilst this noise is happening I have shifted the transmission into neautral and the sound still occurs with the same pitch.
Recently I changed the wheel bearings,perhaps I upset the "Sipders" in the diff?I took the rear diff cover off and jacked up the Axels,ran the Truck with its wheels off the ground.As luck would have it ,the noise didn't happen for the experiment.
However with my foot I was able to slow one turning wheel,untill the diff would lock,however the wheel would spin free again.Ie the diff lock would disengage.
http://www.youtube.com/watch?v=g3TSjotcAkg<!--QuoteEnd--><!--QuoteEEnd-->
I have recently changed all parts inside the differential, mainly because the "sunwheels" (solhjul) where broken. I also had a "sewing machine" noise and there where a lot of slack in the diff (axle turning 1/2 revolution when changing between D and R. I changed bearings and the heavy "lump" (planethjul) in the middle with one salvaged from a parts car. I tighted up the main (inner) bearings so they had some "room" to move but not much. (if its too tight, it would burn up) At first the sewing "noise where bad but this have been better after some driving. And I have heard that this would be normal. Bearings "går seg til" All slack is gone.
You could check out: bearings and if you have too much slack. Use some heay tools, iron rod or something to move things around in the diff.. The sound from the video "dumb dump dump" is normal. Corect oil level would to some degree dampend noise. Diff lock is "oil driven" so you cant check it without oil on the axle.
Remember that these rear axles are pretty robust. If you not going much off road, burn outs ect these axles would run another decade. I have been driving with sounds for several years. But of course its irritaiting!!
