technical

I hit the 500 mile mark on my new rear setup and needed to change the fluid. The auto parts store didn't have much of a selection and I ended up with Mobil 1 LS 75w90 because I wasn't paying $18/qt for Royal Purple and there was only two bottles of Lucas conventional gear lube left on the shelf.

I can't seem to find much consistent information about the Trac-Loc posi unit (here or on the ford sites) and whether synthetic fluid is ok. I managed to forget to add the friction modifier which I can add if necessary even though the Mobil 1 LS supposedly contains the FM. I can hear more noise during slow sharp turns which is fine with me, except if that causes excess wear.

Anyone have an expert opinion? Synthetic yes/no? Add the friction modifier too?

n2ocamaro

The guy that built my center section with a Trac-Loc said no on synthetic fluid. He said use conventional and add the friction modifier

chon79

iTrader: (24)

Is the Track-Loc the Clutch type Posi?

Intercooler2

iTrader: (24)

Yes it is. Normal oil with modifier

chon79

iTrader: (24)

OK cool Also trying to decide on what posi to go with for a 600-650ish (bottlefed) HP H/C/I M6 car.

Bob@BruteSpeed

iTrader: (16)

I'd go with the Wavetrac. I have information at this link on the Wavetrac. https://www.brutespeed.com/rear_end_information.htm Bob

technical

Update:

I got a hold of Strange and they recommend conventional fluid with the additive for the break-in period, but afterwards they said synthetic is ok but definitely add the FM.

LS1-IROC

iTrader: (4)

I used conventional in my trac-loc. You can definatley tell when you don't have enough FM in it