- Oct 14, 2021
- 759
- 731
Well, since yesterday I had my car up on the lift to drain and refill the rear diff for a 4th time. First I'm a little annoyed at the difference in price between dealers for this GM LS diff fluid. Called my usual contact and they only had 2 bottles for like $38 each. Last year I bought 3 bottles for only like $22 each (still have the receipt from Spring 2021). Called another dealer they had none but charge $55 each.
Looked up Tubman online and they were good only $19.xx a bottle but shipping to me in Toronto from Ottawa is like $14 bucks for 3 bottles. Finally I checked Old Mill (Jane/St. Clair) they had lots and was about $25 each so I decided to pick up 3 of them there instead (basically similiar pricing to Tubman with shipping and no waiting).
There's two other brands that I've found that is LS 75w90 gear oil made by Mobil 1 and PetroCanada. I'm wondering if either of these 2 fluids will be the same fluid as the OE GM stuff (my feeling is perhaps the GM LS oil is repackaged M1 LS gear oil but I don't know).
So yesterday aftn. started draining out the gear oil after driving the car a bit, fluid came out fairly warm but not hot and looked slightly darker than the new gold colour fluid so my previous 3 drains is helping to "clean out" whatever gunk might still be in there. As I didn't want my garage to stink of gear oil after I drained out to a steady drip I replaced the plug and poured the old fluid into a container then left the pan under the diff again, removed the plug and left it to drip till today. I collected just under 3 litres of gear oil into the container so when I pump in the new fluid it should be close to 3 or a little over before it starts dripping out of the fill hole.
I might "slightly" lift up the front of the car to put a rear angle at the back to see if more comes out but have to check to see if my jack goes up high enough with my car at the lowest lift point later this morning so we'll see. This one for me should be the last time I'll change gear oil for a few years before needing to do it again. I had only put about 2000kms on the car since this spring after changing a 3rd time and the ZR1 will be going into storage soon after this is done.
Looked up Tubman online and they were good only $19.xx a bottle but shipping to me in Toronto from Ottawa is like $14 bucks for 3 bottles. Finally I checked Old Mill (Jane/St. Clair) they had lots and was about $25 each so I decided to pick up 3 of them there instead (basically similiar pricing to Tubman with shipping and no waiting).
There's two other brands that I've found that is LS 75w90 gear oil made by Mobil 1 and PetroCanada. I'm wondering if either of these 2 fluids will be the same fluid as the OE GM stuff (my feeling is perhaps the GM LS oil is repackaged M1 LS gear oil but I don't know).
So yesterday aftn. started draining out the gear oil after driving the car a bit, fluid came out fairly warm but not hot and looked slightly darker than the new gold colour fluid so my previous 3 drains is helping to "clean out" whatever gunk might still be in there. As I didn't want my garage to stink of gear oil after I drained out to a steady drip I replaced the plug and poured the old fluid into a container then left the pan under the diff again, removed the plug and left it to drip till today. I collected just under 3 litres of gear oil into the container so when I pump in the new fluid it should be close to 3 or a little over before it starts dripping out of the fill hole.
I might "slightly" lift up the front of the car to put a rear angle at the back to see if more comes out but have to check to see if my jack goes up high enough with my car at the lowest lift point later this morning so we'll see. This one for me should be the last time I'll change gear oil for a few years before needing to do it again. I had only put about 2000kms on the car since this spring after changing a 3rd time and the ZR1 will be going into storage soon after this is done.
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