I was at auto zone and noticed delo 75w90 rear diff oil was cheaper than all the conventionals..I was going to get some to change the fluid on the diff in my 82 Buick lesabre RWD..the guy atctge parts counter said it would be too thin..is this true?
Delo 75w90 synthetic rear diff oil in 82 lesabre
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MolaKule
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The parts counter guy uttered a statement out of ignorance.
A synthetic 75W90 has the same viscosity (thickness) as a conventional gear oil of the same rating.
A synthetic 75W90 has the same viscosity (thickness) as a conventional gear oil of the same rating.
He was saying 75w90 was too thin and to use 80w90 instead... I figure its not true...
75W90 is going to be thinner than 80W90 when cold, but the hot specification remains the same. There is no reason you cannot use it.
Too thin for what, a F350 dumpbody?
Originally Posted By: ARCOgraphite
Too thin for what, a F350 dumpbody?
Right?
In reality, that stuff is probably rated for 500k mile OCI in Class 8 trucks. Like the Mobil Delvac I put in my car.
Now, those have several gallons of fluid in each axle, forced lubrication and full-flow filtration, but its definitely not 'too thin'.
Too thin for what, a F350 dumpbody?
Right?
In reality, that stuff is probably rated for 500k mile OCI in Class 8 trucks. Like the Mobil Delvac I put in my car.
Now, those have several gallons of fluid in each axle, forced lubrication and full-flow filtration, but its definitely not 'too thin'.
Originally Posted By: ARCOgraphite
Too thin for what, a F350 dumpbody?
'When cold' = thicker than when hot. It's never going to be 'thinner' than it is when hot.
Too thin for what, a F350 dumpbody?
'When cold' = thicker than when hot. It's never going to be 'thinner' than it is when hot.
Curiously, Toyota recommends an 80W-90 gear oil in the rear differential in my Tundra, and a 75W-90 gear oil in the transfer case and front differential. I don't know why--maybe they can save a few pennies on the many gallons of factory fill in the rears. 75W-90 has worked very well in all three units.
Originally Posted By: Ken2
Curiously, Toyota recommends an 80W-90 gear oil in the rear differential in my Tundra, and a 75W-90 gear oil in the transfer case and front differential. I don't know why--maybe they can save a few pennies on the many gallons of factory fill in the rears. 75W-90 has worked very well in all three units.
Pretty much nailed it.
Curiously, Toyota recommends an 80W-90 gear oil in the rear differential in my Tundra, and a 75W-90 gear oil in the transfer case and front differential. I don't know why--maybe they can save a few pennies on the many gallons of factory fill in the rears. 75W-90 has worked very well in all three units.
Pretty much nailed it.
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