Several questions...

[MajorCavalry]

I currently own a 2015 Lexus GS 350 AWD. Manual calls for 75W85 GL5 for the rear diff and 80W-90 GL5 Hypoid for the front diff.

Was planning on using Redline 75W85 for the rear and Redline 75W90 for the front. Any concerns or possible problem with the different viscosity of the Redline for the front?

Second question. I do not own a lift and cannot slide under the car without raising the car 5-6" . I normally use solid wood ramps that I built layering 2x8's joined with liquid nails.
If I use these ramps to raise the front end (or the rear end) the car will obviously not be level. Any issues draining and refilling using this technique?

Thanks for answering these probably elementary questions.

 

[JLTD]

Probably no worries with the other lube, it will be slightly thinner at low temps, but still the recommended grade at operating temp.

AWD...why not build a second set of identical ramps for the rear? Don't know about the layout of your differentials...depends on the orientation, and which side the drain is located.

 

[Wolf359]

Not being level shouldn't be a problem if you know how much fluid is supposed to go in and add just that amount.

 

[JLTD]

Originally Posted by Wolf359
Not being level shouldn't be a problem if you know how much fluid is supposed to go in and add just that amount.


I think the issue is getting all of the old fluid out… If you drain it in a lot of old fluid remains, that's not a good thing.

 

[JeffKeryk]

Level the car. You don't service the differentials that often.
Redline is good stuff.
I will service our GS differential and transmission soon.
The front tires will be on ramps; the rear will be on stands.