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Full Version: Transmission oil change
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Shell Oil gear oil in my transmission, synthetic, 80-90, that is what Speedco carried. Mobil 1 synthetic in the diffs. Both are quality brands.
Just changed my transmission from synthetic 50w to regular 80w90 and it does shift better. I don't think it will matter much this winter but I will see.
(06-20-2018 )Volvo8873 Wrote: [ -> ]Just changed my transmission from synthetic 50w to regular 80w90 and it does shift better. I don't think it will matter much this winter but I will see.

I noticed the difference immediately. I’m glad Rawze clued me in on this. Shifts much smoother and rarely hangs up now. Very happy!
It's a long way from 50W to 80/90 I'm just curious why the manufacturer would call for 50W if 80/90 is better. Something doesn't add up here.
It's all about mpg. There hasn't been any significant changes to transmissions or their oil galleries in decades.
Just my two cents worth you won't notice that much difference in winter at least I never have and I run In,Mi,Wi,Il,Oh northern Ky
(06-20-2018 )Nilao Wrote: [ -> ]It's all about mpg. There hasn't been any significant changes to transmissions or their oil galleries in decades.

Ahh ok
(06-20-2018 )Waterloo Wrote: [ -> ]
(06-20-2018 )Volvo8873 Wrote: [ -> ]Just changed my transmission from synthetic 50w to regular 80w90 and it does shift better. I don't think it will matter much this winter but I will see.

I noticed the difference immediately. I’m glad Rawze clued me in on this. Shifts much smoother and rarely hangs up now. Very happy!

Now that you say that about it hanging up I realize it doesn't at all since changing it! On the 50w it would all the time. Drove me nuts! LOL
Funny thing is all other countries like Australia, Europe, Asia, India, etc alk specify 50w or 75w90/80w90 as approved viscocities. Only here in the land of the free are we restricted to one weight by the manufacturer.
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