Mechanics

CHEVY REAR DIFFERENTIAL

2000 Chevrolet Blazer

Drive Train Axles Bearings problem
2000 Chevy Blazer 6 cyl Four Wheel Drive Automatic 77500 miles

Just found out that pinion gear is missing a tooth and spiders have some damage to gears. Ring gear looks good. What is the most cost effective way of getting repairs made? Shop that I went to can't make repairs, but told me best course of action would be to replace whole rear with used one, which they can do. Can vehicle be safely driven as is? Only symptom is feeling like you're driving on a washboard when car creeps forward in drive at idle. Otherwise no other symptoms at higher speed. Should I consider going to a transmission shop for repairs? Thanks in advance for your help.
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Profslime
January 9, 2010.



First of all, if the pinion gear is missing a tooth then the ring gear is damaged and/or must be replaced. Ring and pinion gears are a set - you CANNOT interchange them. Even if the ring gear was ok (which I doubt) it must be changed. Damage to both pinion and spider gears indicates that pieces of debris were floating around in the rear. It will be more cost effective to replace the entire unit as compaired to repairing it. The only question is what is your price range -- a junk yard unit will have some miles on it -- call for prices. A new unit will run around $600.00- with zero miles on it and a warranty.
It is not smart or safe to drive this vehicle with a damaged pinion gear and spider gears. The rear WILL eventually sieze and explode. This could cause transmission - transfer case - and engine damage.

Tiny
Pear69
Jan 10, 2010.
Thanks for your quick response! It has been most informative. Shop that did work guesstimated cost of junkyard unit to be in $500.00 range. Sounds like I need to be looking for different shop. They knew of damage but failed to tell me about it. They had done other work to vehicle, new brake lines, two new tires and new diff cover because old one rusted thru and was leaking. I returned a week later when my wife who drives vehicle daily told me about symptoms. A mechanic in shop told me about what they had previously found, but nothing was documented and no one told me previously. They also told me it would be okay to drive car until they could work up estimate. Where can I find new rear for $600 range. Would it be a complete unit or parts to rebuild? Also I am new to the forum and had already contributed upon asking my initial posting. Thank you once again for your help!

Tiny
Profslime
Jan 10, 2010.
The $600 is just an estimate and is for just the parts required for a new rear (labor will be more). If you want to purchase the unit yourself you must know what the gear ratio is, what size the differential is, and how many splines there are on the axle. It is most likely an 8.5 inch rear but you should go to the drivetrain specialists web site. There you can see what is involved with identifying what rear you have. You can also purchase everything you need there. You must also decide what type of traction you want - limited slip or posi. If installing a new unit, I suggest going with a Trutrack with the new stock gear ratio ring -n- pinion and a timken bearing installation kit. If you do not know how to install this init I suggest having a professional do it. DTS has instructions, but if you don't know what you are doing you can easily mess it up. Once again, driving this blazer will lead to more damage.
BTW - be aware when purchasing a new ring -n- pinion gear set. There are different manufacturers. O.E.M. Is the quietest gear set and I suggest O.E.M. But if you are planning on going off roading and stuff like that then Richmond - U.S Strange - AAM gears are what you want. Motive Gears are junk.

Tiny
Pear69
Jan 10, 2010.