Hello and I was talkin to my dads great friend that is in his 90's now and he rebuilds auto trans. He was a GM fluid engineer workin with auto trans and such, and he said way back then and when he left in the 80's that he saw that the FORD ATF was much higher refined than the GM atf. Any truth to this? He is a very good auto trans man also, no [censored], tells ya the way it is and does not take any (censored) and is uprfont and honest. He told me that if I rebuild a gm or ford auto trans to use the JOHN DEERE HY GARD tractor fluid as its some good stuff, as it does not thicken up and maintains viscosity well. Any input would be appreciated, and comments and opinions, and older members here that know about auto transmissions would be welcome. Also, may be lil' off topic, but was reading thru older HOT ROD magazine, and there was a young man that had a 93' mustang with a T-5 manual; he was using mobil 1 10w30 in the trans without a problem.
DEXRON/MERC or FORD ATF
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It doesn't thicken up? Hy-gard is already 50% thicker than ATF.
Up until MerconV and TES295, most Mercon/Dexron specs were similar and overlapping and is why most ATFs were blended to overlap both. So, I won't believe that Ford was better than GM. GM probably wasn't any better than Ford.
And, most newer electronically controlled transmissions won't tolerate a tractor fluid. Some might not even tolerate the change in pressure/flow from ATF that much thicker.
What you could get away with in the 80's, with fluid choices, you can't anymore.
I don't care for motor oil in manual transmissions. Shift quality suffers. There are plenty of good MTF's and MTL's that work better, and are rated GL3 or GL4 for gearbox protection.
Up until MerconV and TES295, most Mercon/Dexron specs were similar and overlapping and is why most ATFs were blended to overlap both. So, I won't believe that Ford was better than GM. GM probably wasn't any better than Ford.
And, most newer electronically controlled transmissions won't tolerate a tractor fluid. Some might not even tolerate the change in pressure/flow from ATF that much thicker.
What you could get away with in the 80's, with fluid choices, you can't anymore.
I don't care for motor oil in manual transmissions. Shift quality suffers. There are plenty of good MTF's and MTL's that work better, and are rated GL3 or GL4 for gearbox protection.
He told me that it maintains its viscosity and does not get like oil when cold or does not thin out. He was talkin bout using it on older gm/ford autos, not newer, though I know a kid running a gto with this tractor fluid and all he cuts it with is like a qt of MMO. Never been rebuilt, no carnage or nothin. I helped him change out the clutch, that was all. Original clutch had like 179k on it. The kid's article in HOT ROD was "tractor master", and he said that using what the T-5 manual called for made shifts grind, and when he used mobil 1 10w30 the grinding stopped and never had a problem. I think it might be cause synthetic is more slippery.
If it was more slippery, then the grind in a manual transmission would be worse. More likely, the thicker 10w30 motor oil, in a manual transmission calling for ATF, will slow down the shift preventing the grind.
If he doesn't have proof of the viscosity via used oil analysis, he is talking out of his ... All fluids thin out or shear over time. Starting thicker isn't necessarily any good. And, there aren't are too many people worrying about those old transmissions anymore.
Whats the point in thinning out a thick fluid back to regular visc with MMO? Just use the ATF.
If he doesn't have proof of the viscosity via used oil analysis, he is talking out of his ... All fluids thin out or shear over time. Starting thicker isn't necessarily any good. And, there aren't are too many people worrying about those old transmissions anymore.
Whats the point in thinning out a thick fluid back to regular visc with MMO? Just use the ATF.
I see, and I guess it is just good then for older transmisions.
The brother of my best friend at the time rebuilt the TH400 in my Buick Gran Sport and told me to use Type F in it. That was 30 years ago and the transmission still works perfectly today.
Yeah I have heard to use type F also. Some guys I talked to at carlisle last fall swore by using the HY GARD fluid. I dont know just what I heard.
MolaKule
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If you are referring to Ford Type "F" it was a 7.5 cSt fluid made for a series of Ford transmissions that didn't need the higher level of friction modification.
Yes, Ford Type F is great for racing or modified transmissions.
Neither Motor oil nor Hyguard nor THF fluids contain the correct balance of additives for modern transmissions.
Yes, Ford Type F is great for racing or modified transmissions.
Neither Motor oil nor Hyguard nor THF fluids contain the correct balance of additives for modern transmissions.
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Thank you and I see this now.
your obedient servant,
adam vasbinder
I apologize to ANYONE here that I offended also in any of my previous posts. I want to learn a LOT more on this wonderful board/site.
your obedient servant,
adam vasbinder
I apologize to ANYONE here that I offended also in any of my previous posts. I want to learn a LOT more on this wonderful board/site.
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