Motorcraft manual transmission oil

[boatcarpenter]

Upon looking everywhere at local autoparts places for specified oil for my three speed transmission for which manual calls for a GL4 oil.All the gear oils I had found was GL5 rated which is not good for your bronze or brass syncros.Came across this recommendation at the BITOG forum.It is a full synthetic oil from your local Ford dealer that cross references with the old spec,and it looks like great stuff.Have had it sitting on truck seat in these -0 temps and stays nice and pourable.Will try to get it in this weekend as current oil is very stiff to shift in these temps.

[fordman]

i was looking at a junkyard 72 the other day and it said to use motorcraft sae50w in the manual transmission. just something i saw on the inside of the glove box door.

[peanutman]

When i had my t85 od tranny rebuilt, my tranny guy said to use standard 80w-90w gear oil. He said i could try synthetic but it would make some of the older tranny's act up. Problem with syncro's or something like that. Keep in mind i live in texas.

[boatcarpenter]

It was a blazing hot day here today first 40 deg. day since November so crawled under truck and pulled drains out of my tranny.Also pulled my OD solenoid off to clean up the contacts and see what I could do about oil getting into it and fouling the contacts up.While tranny was dripping its way empty pulled solenoid apart cleaned it all up with carb cleaner.There is a seal on business end of solenoid that was hardened and allowing the oil to get in so ran to parts store to find the magic seal an oddball it is I found out .307 shaft dia. and .623 outside dia.Carquest looked through the books and could only find .312 inside and .625 outside diameter.Ran to next town where Napa is and the clerk recognized what I was holding right off.He wondered back to parts bin and returned with a small seal with the right inside dia. and too small of a outside but his books showed nothing the right size as well.He also told me he may have a couple solenoids he saved from his old OD transmissions and would dig through his garage and give me a shout and gave me the smaller seal which he said was for a carb shaft.So I ran home with parts in hand with the mission to make it work Ended up turning a piece of ebony on the wood lathe and boring it out to the smaller seal size and put it all together with indian head sealer.
Soldered new wires on to solenoid and tested it and it works as new Finished dumping Fords new high tech oil in it at 11:30 this evening,and took it for a test drive wow what a difference nice solid feel to the column shift can actually drop it into first gear without forcing things.Also second gear the shift lever had a habit of dropping down a little which had me thinking I was going to have to tear the column apart and see what needed replacing,,it no longer does drop down or feel vague.So it looks like the oil will work very well and being a full synthetic should save me a little gas mileage as well and the price is right at around 13 bucks for the 4 pints required.

[averagef250]

Syn works fine with most brass synchronized older trannies. New process sticks don't like it, the synchros don't work as well.

SAE50 does not work, new SAE50 is not the same as what it was in the 70's. It will cook your bearings.

[peanutman]

Thanks dustin for the info on the syn gear oil, may change mine.