i'm sure this has been asked a billion times over but i did a search and it wasn't too specific! what oil is best for my 1990 2wd saph engine and gearbox? it's been run on mobil 1 15/50 for years but a lot of people seem to have issues with that now? also wanting to change the gearbox oil, now i'd always been lead to believe the T5 box ran on pretty much ATF fluid but after looking on the opie oils site they seem to be recomending a 75/90 grade transmission oil?

what are you using folks?

 

The T5 can be run on the 75W90 gear oil, but it will kill the synchro's over time.
The best oil that is the closest to the oil designed/chosen for it is the CASTROL TQ-D, a ATF but a certain variety, available at Halfords, about £9 a litre, you'll need 2.55 litres from empty.
The engine oil really varies a lot, if the engine is a bit old/worn I'd be using a 50 weight or even a 60 weight, 2 that come to mind are Fuchs Titan 5W50 (silkolene pro s), and Millers 10W60.
Ford specified a 5W30, which would spell death to a cossie, if used as most do.
A new/unworn engine would be ok on a 40 weight if driven easily, a oil that is thicker to start with will still be thicker at the same temp as a thinner starting one, hence more protection from surface to surface contact.
tabetha