i wanted to know where to fill the rear differential, i know where the drain plug is but i dont know where to fill it up? i think i need to reseal it so i know that i need to take the case off and was just thinking about putting in a lsd too, do they bolt up??

 

What year is it? As for filling it up, the fill hole is dead in the rear of the housing, same size ratchet as the drain.

 

well its an 84 gs and what kind of oil do i use??

 

Any good or decent 80/90weight will do. Same with the manual transmision.

IIRC, 84 is LSD. unless the GS is different and I missed something somewhere.

 

Heres where you fill it.



At the bottom of the diff is where you drain it.

Oh, you need a special pump to get it in there.

If you have disc brakes, you have LSD. GS has drum so just any gear oil...oh wait i have a pic...


then IF you had LSD the is what you would put in




-Ryan

 

Ryan, do you by any chance have a camera????

 

Is there a significant difference if you fill the rear end while it's on the car. I refilled it when it was on the car and man did that suck, I had to use a funnel and a hose and hold it up high while I waited a long time as the gear oil slowly dripped it's way in. Also, is there a big difference between the regular gear oil and the lsd one, cause I have an lsd and filled it with regular gear oil?

 

It may make a chattering noise without the Limited slip additive, if you have an LSD... Just get the addditive.

Your best bet for filling is to buy one of the quart bottles with the little nipple on top and get a hose. Then just put the hose on the nipple and squeeze the bottle as hard as you can.

They do sell pumps for that purpose, but eh.. $$$

Alternatively, you can buy several feet of hose, hang the bottle upside down with one end of the hose on the nipple. Then crawl under the car with the other end of the hose. Crimp it off to stop the flow. If you're sophisticated, add a ball valve and a check valve to let air into the quart bottle.

 

Oh please, break down and buy the little pump. Its worth the $. Another tip is to warm the oil if its cold out so it flows better. Put it in a bucket of hot water to warm it.

 

I actually like my little upside down bottle trick... I have a large funnel with several feet of hose on it that I used on my 7... Hung it from the latch on the hatch.

Worked nicely. Just gotta have good hatch struts.

I don't wanna spend cash on somehting that'll put in like an ounce at a time... Especially when I have to put gear oil in my truck which takes over 2 gallons all around. (Both front and rear diffs, Transfer case, and tranny.)

 

I've got an 83 gsl LSD with the smaller diameter axles and disc brakes. I'm gathering I should use the mobile 1 synthetic gear oil along with a god LSD oil additive.

Thanks in advance,

Frog

 

You should use ANY 80/90 you wish, They do make the stuff just for lsd rears so you won't need the additive.

 

http://www.racingbeat.com/resultset....rtNumber=11966

So this would work for the tranny AND diff? How many quarts should I buy to do both and where can I find the additive?

- Tech

 

 

Yes, would work perfect. Well if you do both you should buy 5 quarts.

The tranny and diff should take like 2 qts each. You fill them till they overflow from the fill plug.

So..

Drain it.
Plug it.
Fill it till it starts comming out of the fill hole. Dont over fill it, as soon as it comes out let it go for a little then plug it.

Here step by step just for you...

1. Drain Plug


2. Fill Plug


3. Gear Oil Pump **A MUST !** (some have their own methods)


You can get the LSD additive at parts stores. I got the GM one from the dealer.


Good luck !
-Ryan

 

Fill till they over flow? That's the first time I have ever heard that. I never fill that full. Fill till yo can stick your finger in the hole bend the first knuckle and feel it on the tip off your finger has been the rule for over 30 yrs that I have been working on cars. However, things could be different now.

 

Fill it till it runs out. Too much is better than not enough. I use Royal Purple. It's about $7.50 a qt, but it really does a good job. Some use Redline or other syntecs.

 

I'm not sure about that, I fill to specs, from memory 1.7 in the diff(LSD), 2.1 in the tranny. Some years differ, and your results might as well.

 

To much is NOT better! Sure way to blow seals.

 

You are not going to blow a seal if it's filled level to the fill plug. What will cause you to blow a seal would be if your vents are plugged, which should be checked every time you service the vehicle anyway.

 

Tell that to someone else. Did it on my 85 Peterbuilt. You tend to learn sfter a major F*#k up.