Differential Oil change
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Instructor
Joined: Apr 2019
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Differential Oil change
I have a 2017 Non Z51 Stingray. I believe it is time to change the rear gear oil. I will be using Amsoil 75/90 Severe gear oil and I am wondering, has anyone found it necessary to Add Friction Modifiers to this oil. It appears in the Ads that this material is already contained in the oil and not needed but I figure asking does not hurt anything.
Also is too much Friction Modifier a bad thing or no difference. Thanks in advance
Also is too much Friction Modifier a bad thing or no difference. Thanks in advance
Last edited by zzcop8; Jul 9, 2025 at 02:24 PM.
Drifting
Joined: Sep 2019
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From: Colo Spgs, CO
Amsoil SEVERE GEAR 75W-90 contains friction modifiers for limited-slip applications, so no additional is required.
Too much friction modifier can cause cause slipping, chatter, and/or unusual wear.
Too much friction modifier can cause cause slipping, chatter, and/or unusual wear.
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From: Sarasota, Florida
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I have a 2017 Non Z51 Stingray. I believe it is time to change the rear gear oil. I will be using Amsoil 75/90 Severe gear oil and I am wondering, has anyone found it necessary to Add Friction Modifiers to this oil. It appears in the Ads that this material is already contained in the oil and not needed but I figure asking does not hurt anything.
Also is too much Friction Modifier a bad thing or no difference. Thanks in advance
Also is too much Friction Modifier a bad thing or no difference. Thanks in advance
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Joined: Aug 2011
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From: GREER SC
Safety Car
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From: Chester VA
In the case of cars with Z51 (which fortunately for the OP he doesn't have) the presence of an additional rear end cooler interferes with easy access to the fill and drain plugs.
I found that out last year when I raised my car on quickjacks to do the change and found I couldn't get to either. I double-checked on the youtube videos I'd watched, and even though they were filmed using Z06 or Grand Sports, there was no cooler in the way. The videos made it look like an easy drain-and-fill job. So why did I have that cooler blocking my progress?
Further digging revealed it to be a Z51 piece, placed there for extra cooling while tracking the car.
Maybe if I had the car completely up on a lift, plus maybe some additional tools, I could have done it. But nope. Ended up as a dealer job.
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Not necessarily.
In the case of cars with Z51 (which fortunately for the OP he doesn't have) the presence of an additional rear end cooler interferes with easy access to the fill and drain plugs.
I found that out last year when I raised my car on quickjacks to do the change and found I couldn't get to either. I double-checked on the youtube videos I'd watched, and even though they were filmed using Z06 or Grand Sports, there was no cooler in the way. The videos made it look like an easy drain-and-fill job. So why did I have that cooler blocking my progress?
Further digging revealed it to be a Z51 piece, placed there for extra cooling while tracking the car.
Maybe if I had the car completely up on a lift, plus maybe some additional tools, I could have done it. But nope. Ended up as a dealer job.
In the case of cars with Z51 (which fortunately for the OP he doesn't have) the presence of an additional rear end cooler interferes with easy access to the fill and drain plugs.
I found that out last year when I raised my car on quickjacks to do the change and found I couldn't get to either. I double-checked on the youtube videos I'd watched, and even though they were filmed using Z06 or Grand Sports, there was no cooler in the way. The videos made it look like an easy drain-and-fill job. So why did I have that cooler blocking my progress?
Further digging revealed it to be a Z51 piece, placed there for extra cooling while tracking the car.
Maybe if I had the car completely up on a lift, plus maybe some additional tools, I could have done it. But nope. Ended up as a dealer job.
I did my 2019 Z06 a couple of years ago. Not fun by a long shot. A variety of socket drive adapters and smaller hands and fingers helps the cause at the Fill plug.
Thread Starter
Instructor
Joined: Apr 2019
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Likes: 39
Thanks for the replies, got the oil changed. If you have a rear sway bar like I do it helps to disconnect it and push it up out of the way. This gives you quite a bit more working room.
A big THANKS to ever invented the Oil in the bag, made adding the oil much easier than a bottle that would never fit in the space allowed.
A big THANKS to ever invented the Oil in the bag, made adding the oil much easier than a bottle that would never fit in the space allowed.
