Noticed a small puddle in my driveway this week, more than a drip. I took alook under my 96 Blazer and it appears to be the read differential. I will try to tighten the bolts for it but worst cast I will have to pull the cover, replace the gasket then fill. Question is how much fluid does the rear differnential need. I don't want to be half way into this and need to walk to the local parts store!

Thanks,

m.

 

when you pull out the little screw...you should be able to put your pinky in the hole and have oil to the first knuckle....you might have to get the seal replaced..that usualy cots about 100 if you have someone do it....your differential has to be full otherwise you run the risk of loosing lube to your rear axle and bearings......causing you to have a very very very costly repair....(as in finding a whole new rear end) I know that the differential dosen't tolerate low oil at all....specialy if it's leaking that bad....

 

The rear will take 2qts so if you get 3qts youll be safe.

 

Last older ten bolt I did had a bad axle seal also. I replaced all and even managed to keep the spider in there. Yeah I'd buy three, cause it spills when working under there.

You are sure its the gasket?? Do you have a regular rear or a posi?? Do you have four wheel drive? There is a special additive for GM rears. Have never used it but it says its required. Posi rears take a special, different from the standard, lube also. Be sure you get the right ingredients.

Only problem I have seen is the way the 3/8 drive "hole" is for filling it. Be darn careful to not stick a regular extension in yours. Cheap extensions are sorta rounded both at the end and on the edges and may not catch well enough. If the extension does not "catch" right then you'll strip out the square drive hole and be up a creek. The best solution is to have the right tool and not simply stick an extension in there. A socket is made for the job, though sometimes hard to find and it seems so so so easy to just stick that extension in there????????????? If its tight, you'll regret it.

Of course i change mine over to either an "outie" or an allen wrench plug. perhaps you'll get lucky and already have one of those. i dont know what the later models have. Havent looked at my 95. Writing about our 87.

 

There are gear oils, that allow you to not have to use the additive, pennzoil Gearplus 80W-90 GL5, lucas oil heavy duty 80/90 are just a couple of manufactures. It will also say on the bottles.

 

Fill up to the lower threads on the fill plug. Pick up 3 bottles. In case you have to drain it again. You can return the extra at another time. Or drain and change the front while your under there.

 

Thanks for the feedback, 3 liters it will be.

Proble might be worse that I thought. On a closer look the fluid stain on bottom of the differential goes from the cover to the driveshaft connection. Is there a seal in there that can be serviced also or is this a off to the mechanic job now? As stated previous I am a novice willing to try.

M.

 

SO it may be originating from the pinion area? You'll have to remove the drive shaft to pull the pinion/yoke out.

 

Thanks, do you feel this is a big ticket item? I is beyound my skills presently.

Thanks,

m.

 

I don't think it's as much as a matter of skills....but more the equipment and tools needed along with the time....I got my diff. bearing fixed for 100 dollars when mine was leaking....if you had a garage with the right equipment...the merk manuel even goes over it.....otherwise I would have someone else do it....100 dollars is worth not doing it myself