Gear Oil Change

How hard is it to change the gear oil in our cars? It's somewhat rough when I shift and I think my car's ready for a change. I have a '94 SL.

its fairly easy, you have 2 filler plugs, one on the transfer box and one on the front of the gearbox near the reversing switch. i had trouble getting my one off on the gearbox i think the hulk had done mine up.

you have to take down the engine shield from underneath but apart from that i think its plain sailing after that.

sl's dont have a transfer case, and I didnt have to remove anything to change mine.

is the light on the dash for the t-cast or the rear diff?

sl's dont have a transfer case, and I didnt have to remove anything to change mine.

Okay, this discussion about the transaxle, transfer case, and rear differential is what kept me from changing it over the summer because I got confused as to what my car has and what it doesn't. How many areas will I have to change for a '94 SL? Do I have all three? Or do I just have to worry about the transaxle? Thanks.

mike, what light on the dash are you talking about.
there is the 4ws oil light that is actually just your power stearing fluid
there is the oil light, which is engine oil
is there another one lighting up?

slade, the only gear oil you have is in your transaxle, if its a manual you have one drain and one fill plug, drain it, then pump new gear oil into the fill plug. When it starts to come out the fill hole you are done, just make sure the car is close to level when you do this.

Thanks talskinyguy. That's gonna be a lot of help during the process as I won't have to look all over the place for stuff that isn't there. Now to choose a type of oil....what kind do you recommend? :)

sycromesh, i think its a GM branded oil, but its designed for MT's

lol this thread is funny with all the confusion...use 75W-90, I believe that's what it calls for. I put 80W-90 in mine but that's because I was too lazy to go back to Autozone to get the 75W-90. The drain plug is on the bottom of the transaxle facing the passenger front tire, and the fill plug is near the middle of the transaxle facing the front bumper. If I remember right the drain plug is a 24mm plug so you need a big wrench or socket.

im pretty sure mine is 17 or 19, they are deffinatly not 24 because i only have wrenches up to 22

maybe i got a freak transmission...it was a swap, who knows.

sycromesh, i think its a GM branded oil, but its designed for MT's

I read a couple places that mixed 2 types of oil for the transaxle...do you guys suggest doing that as well? Also, I've heard of the Penzoil Sycromesh but haven't heard one from GM. Which one is better? Or it doesn't matter?

im gonna guess that the mixing is for the 3S's that have limited-slip? There's usually an additive you have to put in with LSD's.

sl's dont have a transfer case, and I didnt have to remove anything to change mine.


how very true, guess i didn't read the sl bit doh!!! :banghead:

Is it true that Penzoil uses recycled oil? :o/