ATF change TH400
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Pro
Joined: Nov 2023
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From: Aubrey TX
ATF change TH400
Im still sorting out brakes but in the meantime, while waiting on parts, I am going to change the ATF. The fluid is at least 20 years old. Im not finding Dex2 or 3 at any parts store so Im asking what you guys are using and how its working out so far.
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Old school method is to use Type F to firm up shifts even more. Type F is considered a "high impact' fluid and Dexron is a "high lubricity" fluid designed to smooth the shifts. Both work fine but have different feels on shifts. Race guys use some tractor fluid also.
The T-400 is a tank of a tough trans.
JIM
The T-400 is a tank of a tough trans.
JIM
Le Mans Master
Joined: Oct 2007
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From: RI, Now Franklin/Nashville TN
Old school method is to use Type F to firm up shifts even more. Type F is considered a "high impact' fluid and Dexron is a "high lubricity" fluid designed to smooth the shifts. Both work fine but have different feels on shifts. Race guys use some tractor fluid also.
The T-400 is a tank of a tough trans.
JIM
The T-400 is a tank of a tough trans.
JIM
Agree 100% ^^^^^
A built 350 trans is not as good as a stock Turbo 400 a transmission expert told me years ago!
I used Ford Type F in my Nova SS turbo 350 from 1978 to 1990 when I sold that car and literally beat the heck out of it with zero issues at 170,000 miles on the OEM tranny. I ran 2 stand alone coolers (no radiator cooling) in the grille and changed the fluid and filter OFTEN with zero issues.
As mentioned Dexron VI is backward compatible.
You can use either Ford Type F or Dexron VI since the fluid is not nearly as important as changing the filter and fluid often and keeping the fluid cool (run a double stack cooler) with no radiator cooling.
I have used universal synthetic global trans fluids in several cars over the years, currently and in the past, including Mobil1 synthetic ATF, Sunoco Global Trans Fluid (only commercially available), and Valvoline Maxlife (walmart) in various cars including Lexus, Audi, and Ford Mustang GT. ZERO issues in any car!
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From: Connecticut, USA
Old school method is to use Type F to firm up shifts even more. Type F is considered a "high impact' fluid and Dexron is a "high lubricity" fluid designed to smooth the shifts. Both work fine but have different feels on shifts. Race guys use some tractor fluid also.
The T-400 is a tank of a tough trans.
JIM
The T-400 is a tank of a tough trans.
JIM
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When mine came out of warranty in the summer of '77 the 1st thing I did was install a B&M shift kit with Trick Shift fluid.
78k later I'm still barking 2nd gear...
78k later I'm still barking 2nd gear...