nelstomlinson
Full Access Member
Heh, the Redline ATF claims 70W80 on the gear oil scale. Pretty close to the MTL.
Great! Then 75w80 is perfect. It seems most people don't know that 80w gear oil is roughly the same viscosity as 30w engine oil. Check this out:I would think 75W would be too thick to get between the bearings. Ford ran the ATF (usually 10w) in order to meet CAFE standard for fleet fuel mileage, but I think it is too thin. 2 tow truck owners I spoke with have had issues with their ZF5 and ATF (10w). After they switched to 30W they doubled the life of the transmission.
Good point for future readers, though I was just trying to point out that the MTL was rated at 75-80 and that was perfect for our ZF's as it's a gear oil rating, equivalent to somewhere between a 20 and 30 weight engine oil.Something to watch out for is that gear oils with sulfur can damage brass gears like synchros. Look for a gear oil that claims to be safe for yellow metals.
I also looked at RockAuto but I couldn't find every synchro(maybe I'm just a goober). Most importantly I couldn't find the 2-3 synchro on their website and that's my worst by far.
I definitely will keep them in mind for the other bits that are worn out once I have it apart.
I wish I could get a cheap spare like you did so I could rebuild and still have a working pickup. In my case I won't be able to. BUT, I have 3 vehicles so it should be OK.
Dang it's nuts how location makes all the difference. I'd grab a 7.3 ZF-6 in no time if that were the case. But around here they are all 1200+. At least that I can find.I noticed the same thing around here, everyone wants $1000 for a used zf-5 that probably needs synchros. The strange thing is I was having no trouble finding zf-6 trannys for half that.