transmission oil

[Ray Greene]

I presently have 90 weight oil in my transmission, I think this is to thick, particularly here in the chilly Northeast. After reading other threads here, I see 10/40 or 20/50 motor oil is recommended. Would it follow that a synthetic motorl oil, i.e; Mobil 1 or similar product would do a better job? I was thinking about the ability of synthetic oil to remain more "fluid" at lower tempertures, thereby allowing easier overdrive operation and remaining cooler at highway speeds in the summer?
Thanks, Ray

 

[w. scott brunkhurst]

The BMC manual recommends 20W/30 or 30W oil for all conditions in the tranny and OD. I have been using 40W oil and have had no problems with down shifting, but I do not have OD.

SB

 

[jtb55]

I and at least one other AH 100 vintage racer use Red Line MTL. jtb55

 

[Dave Russell]

Hi Ray,
If you do a search for "Redline" under Austin-Healey, you will find several prior discussions on this subject.

Just click on "Search" at the top of the page & go from there. Or just click on this link;
https://www.britishcarforum.com/cgi-bin/ultimatebb.cgi?ubb=search&search_forum=1
D

[ 02-17-2004: Message edited by: Dave Russell ]</p>

 

[JMC]

I use 30W in my 100-6 which has overdrive and have found that it works just fine.