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transmission oil

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transmission oil

Postby andrewward » Tue Aug 31, 2021 6:43 pm

hi, can anyone please tell me what transmission/transfer case oil to use on a 1991 MU 4jb1 2.8 TD ? thanks
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Re: transmission oil

Postby geeves » Wed Sep 01, 2021 5:47 pm

Are we talking manual or auto?
Auto is easy Dexron 3 auto trans oil for both.
Manual The book says use the same grade engine oil as you run in the engine. However this isnt a great choice because most modern engine oils have friction modifiers which coat the syncros resulting in hard shifting cold. If you can get a cheap engine oil this should work and it is what I had in my 89 bighorn for many years. Some people use dexron3 ATF and it seems to work ok but it does have a tendency to find weak seals and leak. Most of the experts here suggest a gear oil designed for 5 speed gearboxes. Look up Castrol VMX for a specification. Ive just put a Penrite equivalent in my current bighorn and it seems to work ok. No idea though what the oil was previously in there though. It was light brown. Thought it might be water contamination but it did not separate after storing a sample for 4 days
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: transmission oil

Postby andrewward » Thu Sep 02, 2021 7:51 pm

Thanks Greeves, mine is a 5 speed manual, I used to use 15w40, now I use Silcolene 20w50 specific for vintage cars and trucks, used to have blowbye issues now it runs fine with that oil. Not sure what's in the transmission !, the mechanics here have no idea what to put in there because these trucks are rare here and there is no information anywhere. So in your opinion shall use the Silcolene or the ones you mentioned ? thanks
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Re: transmission oil

Postby geeves » Fri Sep 03, 2021 5:33 pm

Never heard of that oil and google gave me 10 different oils with that name. Can you post a picture of the label please
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: transmission oil

Postby andrewward » Sat Sep 04, 2021 4:04 pm

though it says it's for motorcycle oil, it is also used for commercial vehicles label on the tin https://www.silkolene.com/motorcycle/cl ... be-20w-50/
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Re: transmission oil

Postby geeves » Sun Sep 05, 2021 6:25 am

API SF/CC
That is not suitable as engine oil in a diesel. Minimum spec is CD but I would look for CH4 or better for the engine. Also use a diesel specific oil as they have more detergent than petrol oils and diesels are dirty
Gearbox though it should be ok although I would suspect as its a niche oil its expensive for what it is. Use an oil suitable for 5 speed gearboxes
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: transmission oil

Postby andrewward » Sat Sep 11, 2021 4:19 pm

yes thanks, I flushed the engine oil, bought the Total 5000 diesel oil 15w40 putting the into my engine and tranny, may I ask what oil to use for the diff, it says here gl-5hypod sae 140w is that correct ? temperatures here are 11-15c in winter to 35-40c in summer average, thanks
andrewward
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Re: transmission oil

Postby geeves » Sat Sep 11, 2021 5:32 pm

On the plate on the firewall under the bonnet you have a build plate. This has the build codes for what is in your car. On that do you have the code G80? If no your choice of oil is fine. If noot you need an oil suitable for LSD differentials. If in doubt use lsd oil
Sanding your knuckles before starting work can help. That way you cant skin them
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geeves
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