TH400 - Type F or ???

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Anyone using it here on their TH400? I have read some good stuff about it and wanted to hear your thoughts. Mine is making some loud clunks when I put it into gear and reverse also. Other than that, it seems to shift okay. PO said it has 79K original miles in the 86' K30.

I will be adding a larger fluid capacity pan that also has cooling fins. I will also add a bottle of Lubeuard Red also.

Any hep will be appreciated!
 
Originally Posted By: TooManyWheels
Regardless of what the manual specs, there is no reason not to run Type F in a T-400 if you like more definite shifts.


That was one of the things that interested me to begin with. I'm curious of the long run using Type F?
 
well, as an example I had a 78 firebird that was a drag car. Built 400 ci and a TH 400 that was ultra built, very high pressure pump, etc.

Running lower 11's on street tires, higher 10's on a slick. Just switching to type F fluid on the advice of my trans guy was good for almost 2 tenths!

I would sometimes run it on the street but you had to be very careful not to blow away the tires on the 1-2 shift. This car really hooked up hard and broke 3 TH350's in a month till I built the TH400 for it.

Trans was working fine years later when sold.
 
Why would you run a Ford fluid in a GM transmission?? I`m sorry but my mind just wouldnt let me entertain the idea.
 
Originally Posted By: lexus114
Why would you run a Ford fluid in a GM transmission?? I`m sorry but my mind just wouldnt let me entertain the idea.


Have you ever run Non-Lexus oil in your Lexus?
 
Originally Posted By: lexus114
Why would you run a Ford fluid in a GM transmission?? I`m sorry but my mind just wouldnt let me entertain the idea.


It was done strictly for harder and faster shifts. It did not seem to hurt the gearbox even with 500 foot pounds of torque running through it.
 
I think I would just go with something like B&M trickshift...specifically designed for faster shift in a older GM trans...and then you can stop worrying about whether or not Type F will hurt it...
 
Thanks folks I appreciate the input. Seems like plenty of people have used Type F over the years and there have been no problems that I have found. I like the idea of a more firm shift so what the heck... I'm going to replace when I install the new pan in a few weeks.
 
My BIL has two S-10's, one a daily driver and one a racetruck with a 358. We use my type F in the S-10 race truck which has a TH400 for racing, but regular DexronIII in his daily driver with the 4.3L.

The TH400 in my opinion is a very good transmission behind small blocks for racing.

Some history:
http://www.advanceadapters.com/tech-vault/gm-th400/
 
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I am no racer that's for sure but will it cause any issues with normal driving (Mixed city/highway/some towing)? Or should I stay with plain ol' Dextron IV? I certainly don't want to cause any more problems. I just haven't found anything negative about running the Type F. Thanks for all the input!
 
I used to run a TH400 on the street only. But I ran Dexron II. Never messed with the type F.

I would say with the issues you have that the type of fluid is not your top priority right now. Getting your trans working properly is job 1.

I would say
Originally Posted By: sw99
I am no racer that's for sure but will it cause any issues with normal driving (Mixed city/highway/some towing)? Or should I stay with plain ol' Dextron IV? I certainly don't want to cause any more problems. I just haven't found anything negative about running the Type F. Thanks for all the input!
 
Originally Posted By: Astro14
I think I would just go with something like B&M trickshift...specifically designed for faster shift in a older GM trans...and then you can stop worrying about whether or not Type F will hurt it...


I was told that B&M Trick Shift is Type F with blue dye.
 
Originally Posted By: oilboy123


I would say with the issues you have that the type of fluid is not your top priority right now. Getting your trans working properly is job 1.



Clunks from below when changing direction of engagement is most likely U-Joints, not transmission.
 
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