Shop put 80w90 vs 75w90 in.

[EMT_760]

Took my 14 Nissan Xterra into a driveline shop today to have my rear diff inspected for a whine on the power side at 60mph. Everything checked out according to them, backlash, etc. Possibly the gearset is worn but the cost is prohibitive to rebuild. ( $2500. 00) vs finding one at a junkyard.

The mechanic said he used 80W90 (GL4) vs 75w90 in my rear diff. I'm planning on dumping it out soon. Any harm in using 80w90 vs 75w90?

 

[Rand]

are you sure it wasnt gl-5?

There would be harm if its GL-4

if thats a typo.
you might lose a TINY bit of mpg but not much in California.

 

[EMT_760]

are you sure it wasnt gl-5?

There would be harm if its GL-4

if thats a typo.
you might lose a TINY bit of mpg but not much in California.

What type of harm? Its a open diff. No LSD. Petty sure they said GL4.. I could be wrong.

Edit. They said it was a GL5 on the phone.

 

[GSCJR]

It's fine. My Toyota calls for 75w-85 and I've been using 80w-90 in the diff and T/C for years without incident.

 

[nwjones18]

Its fine.

 

[samven]

You just got the conventional instead of the synthetic but I have noticed that on occasion the conventional ran quieter. You will just have to run it and judge for yourself.

 

[JimPghPA]

EMT-760, I don't have a degree in tribology, but with engine oil in a warmer climate the first number being higher would not be of any concern, so it is probably the same with gear oil. In fact the smaller the spread between the first and second number the less likely the oil is to shear in high stress use like between gears. So unless you live in North California or might be traveling someplace where the ambient is very cold, you might be better off leaving it in.

 

[aquariuscsm]

Throw some Amsoil Severe Gear 75W-110 in there.

 

[JMJNet]

It is within the tolerance aka range.
You know that anything mechanical are designed based on tolerances NOT absolute.
If it is not designed with tolerance, the engine will fall apart as soon as oil is poured into it.
Because the oil is not exactly the same even if it comes from the same batch from the same factory of the same brand and viscosity.

 

[haggler]

Strictly the viscosity, no. The first number is cold anyway. But if the diff calls for GF5 instead of GF4 then I would replace with correct spec.

 

[Greasymechtech]

Nissan recommends synthetic. Unless the 80w90 installed was a synthetic, I'd change it out.

And, with some of the diff issues I've seen with Nissan, I'd 2nd that 75w110 recommendation or step up to a 75w140.

 

[AutoMechanic]

It’s fine in my opinion.