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I have an 85 with the 3/od trans. When it's cold it really doen't want to shift, not a big deal but aggravating. After it warms up a little it shifts fine. Question is, has anyone used synthetic tranny oil in one of these? Is one brand better than the other? I want to go full synthetic motor/trans/rear but need to do a little resealing on the motor first so just the trans and rear for now.
I use synthetic in my manual transmission, rear end, brakes, clutch, grease fittings, and sometimes I use the Motorcraft synthetic blend motor oil. I have found that it works better and lasts longer.
I use synthetics in my 18 wheeler just wasn't sure whether or not it was a good idea in the pickup. One of these days I'll get around to resealing my 300/6 so I can change it over to.
Thanks again.
I use synthetics in my 18 wheeler just wasn't sure whether or not it was a good idea in the pickup. One of these days I'll get around to resealing my 300/6 so I can change it over to.
Thanks again.
As far as the engine oil, I don't use synthetic all the time. Or, sometimes I will just add a quart or two to go along with the rest of the oil during an oil change, sometimes none at all. And, I've never really had a leak from using it.
Just going from my past experience with the motor in my 18 wheeler. Tried to swap over to synthetic on it. I found that on an older motor, over 1 million miles, it would find places to leak that weren't there with regular oil. So just figured I would wait till I got the 300 resealed.
I have tried them all (almost), and the winners are:
Shell Rotella T 10W-30 (Year round nothing else near my truck)
Pennzoil Synchromesh (GM also makes Synchromesh Transmission Fluid, but haven't tried it)
50w is the other option (But I dont like it). Most of the other crap sold locally will cause the brass synchro rings to corrode (assuming you have them), and if they corrode they wont line up. That and THICK crap that retains heat are the things you want to avoid.
Just going from my past experience with the motor in my 18 wheeler. Tried to swap over to synthetic on it. I found that on an older motor, over 1 million miles, it would find places to leak that weren't there with regular oil. So just figured I would wait till I got the 300 resealed.
I have always been told that 75,000 miles is the cut off to switch from regular oil to synthetic in a standard motor. If you try to switch to a full synthetic after 75,000 then it will leak out since seals, gaskets, etc are use to the standard weight oil.
Never heard that but guess it does make sense. I have heard that adding 1 quart with a standard oil change will give you about 75% of the advantage of running full synthetic so maybe will try that.
my highboy loved just having fresh oil, after a change I could get it out of gear going down the road w/o using the clutch.
however I too would go ahead and use synthetics in tranny's and diffs. and I think that the leaks people talk about would have been there shortly with dino oil, and needed to be replaced anyways... more old wives tale/urban legend than fact.