Different Oil Grade for Engine with Different Final Drive

[prelude_h22]

Hi All

Just a quick question. I recently changed my final drive in my H22A8 M2P4 gearbox to an mfactory 4.64 final drive.

The engine revs alot higher than usual now i.e. motorway crusing and general driving etc.

Would i need a higher specification oil for the engine i.e. ester based type etc.

I am currently using motul x-cess 5w 40.
Would it be best to go to 10w 40 or get something more like this
http://www.opieoils.co.uk/p-73732-mille ... e-oil.aspx
or is the current oil i am using fine

I have been using 5w 40 for over 6 years - should i be using 10w 40 ??
Engine is just under 70k miles

Cheers all

[wurlycorner]

I wouldn't worry about the change in final drive needing a change in engine oil - you haven't changed your engine max rpm, so your engine is still operating within its design limits. Another way of thinking about it is that if this was a standard FD lude in Germany doing autobahn driving, it would be running around the same rpm as you? And that would be 'normal'.

When your engine is up to temp (which it will be for motorway driving?) it's using the 40 viscocity rating, so changing from 5w40 to 10w40 will make no difference here really.

That aside, the ideal spec oil for ludes in the UK climate is 10w40 according to the service manual, so that might be a reason for changing. 5w40 won't do any harm though - it's when people drop the upper viscocity rating over here that I think they're nuts...

[prelude_h22]

Nice one Wurlycorner.
Thanks for the explanation. Helps alot