Hey all just wanna ask if you think it would be benneficial to change out the rear end fluid on my 07 gmc sierra classic? I know it already has synthetic from the factory but if theres better oil out there I'd like to change it. thanks.
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Hey all just wanna ask if you think it would be benneficial to change out the rear end fluid on my 07 gmc sierra classic? I know it already has synthetic from the factory but if theres better oil out there I'd like to change it. thanks.
I am doing the same thing on my 06 Yukon. But the only 75w90 I have found that meets the GM spec is Redline 75w90. The GM "grape juice" scented synthetic lubricant is $25 a quart. Redline is under $10. Note: I contacted Mobil and they said Mobil1 75w90 does NOT meet the GM spec. I don't know if amsoil does either but you need to check your owners manual and get the spec number and check it. Amsoil just released a 75w110 oil which looks very promising. But I would check with their tech support 800 number first.
Actually if you PM "pablo" he is the amsoil rep here and he will look it up for you. I think the new 75w110 is $12. That is what I'll probably get after I use my grape juice up.
The factory 'synthetic' 75w-90 was black and nasty looking on my 2005 trailblazer when I changed it out summer of 2006 at around 20Kmi. I used M1 75w-90. The diff cover on mine had a sweet reusable metal/rubber gasket (AAM rear).
Yes the new GM sythetic 75w90 is "grape scented". Apparently the guys at GM don't like the sulphur smell anymore. Now it's dubbed "grape juice". I dodn't make this up...
If you are going to use Amsoil ( which I probably will next time around)check out the new 75w110 they released last week...very cool for the GM application IMO..