Transmission fluid

[Harry 6674]

John Deere HyGard low/vis with a touch of F for color.

[ss3011]

I recommend Castrol TransMax (which is also marketed as Allison TransSynd) , or Redline D4 . These fluids are basically a Dextron equivalent.

One thing that I noticed is the synthetics seem to perform the same all day long, where the mineral based (non-synthetics) seem to be slower on the first run of the day.

The friction package built into Dextron oils compared to Ford type F is quite different. Dextron has a higher static coefficient of friction, then Ford type F, which basically means it holds the clutches without slipping, better then type F . If you run lower line pressures in the transmission, this could be plus !

[jmantle]

Originally Posted by ss3011

I recommend Castrol TransMax (which is also marketed as Allison TransSynd) , or Redline D4 . These fluids are basically a Dextron equivalent.

One thing that I noticed is the synthetics seem to perform the same all day long, where the mineral based (non-synthetics) seem to be slower on the first run of the day.

The friction package built into Dextron oils compared to Ford type F is quite different. Dextron has a higher static coefficient of friction, then Ford type F, which basically means it holds the clutches without slipping, better then type F . If you run lower line pressures in the transmission, this could be plus !

Type F doesn't have any friction modifiers, Ford took them out of the Type A in the mid 60's to cover up some design issues with the C4. I agree with you on the synthetics, they do seem to be more consistent between hot and cold and I run and recommend to my customers to run them. I like the Transynd type fluids because they are full synthetic, meet Dexron III friction properties and are a higher viscosity than some of the newer passenger car fluids. Check out TES 295 on Allison's website, it gives a full list of approved fluids that meet the same specs as Transynd.
The attached article explains some interesting facts about tranny fluids.

http://www.aftonchemical.com/Insight...ATFspreads.pdf

Jim Mantle V/SA 6632

[ATI Performance Products]

If you guys are running a Metric trans you must be looking for all the ET you can save? Why would you put a 30 weight trans fluid in it then such as the Lucas or normal off the shelf Petroleum Type F fluid? I think the Dex 5 and 6 stuff is less than 30 but more than 20 and it is a really good fluid but no Type F in it. Nothing is wrong with either of the others but from an ET standpoint you are giving some up.

20 weight, or less, gets used on huge HP cars that don't mind changing it often. Cars like the Challenger and COPO run our 20 weight all season without issue as do thousands of other racers. Our Super F is 20 weight and the Max duty is 30 weight and we have the best price available for a true 100% Synthetic, with full Type F friction modifiers. If nothing else find yourself a good 20 weight to try. In our Challenger, at MIR, in 90 deg weather, dumping out Castrol Type F and putting in our Super F 20 weight was .02 quicker. No reason other than its Thinner. Being synthetic it usually would take 5 runs back to back with normal Super F to get to 220 deg. After the same 5 runs with Super F, being synthetic it was 180.

Originally Posted by jmantle

Type F doesn't have any friction modifiers, Ford took them out of the Type A in the mid 60's to cover up some design issues with the C4. I agree with you on the synthetics, they do seem to be more consistent between hot and cold and I run and recommend to my customers to run them. I like the Transynd type fluids because they are full synthetic, meet Dexron III friction properties and are a higher viscosity than some of the newer passenger car fluids. Check out TES 295 on Allison's website, it gives a full list of approved fluids that meet the same specs as Transynd.
The attached article explains some interesting facts about tranny fluids.

http://www.aftonchemical.com/Insight...ATFspreads.pdf

Jim Mantle V/SA 6632