Trick shift fluid

[76zimmer]

I've heard a few say this fluid is the stuff to have, making shifts firmer. Can the same be said for type F? I was considering a flush with type F then switching to the Trick shift. It has regular Dexron ll in it now, and my 2-3 shift is sliding into gear instead of a firm shift.

 

[k20]

Ive heard the trick shift is pretty much just type F

 

[4by4bygod]

I've heard a few say this fluid is the stuff to have, making shifts firmer. Can the same be said for type F? I was considering a flush with type F then switching to the Trick shift. It has regular Dexron ll in it now, and my 2-3 shift is sliding into gear instead of a firm shift.

How many miles on the tranny? How many miles on the dexron that's in there now? do you have an auxillary cooler? do any towing?

the dexron, type F , and the trickshift are all pretty much the same as far as what ingredients are in it, ( meaning which friction modifiers & anti wear additives they use - phosphorus, sulfur, zinc ), but where they differ is in the amount of these ingredients. In that light, the type F & trickshift are similar, as they contain more, thus giving you the firmer shifts.

When you say " sliding into gear", do you mean actual slipping?

If so, what comes to mind is this.. you can't fix a hardware problem with software.. slipping heats the fluid, so if you don't fix why it's slipping,( from worn internals, being out of adjustment ) your new fluid will cook, and the additives will drop out of the fluid anyway, and you haven't solved anything..

If it's slipping because the fluid is or has been toast for awhile, just changing it with dexron may solve it. maybe slap a cooler in there.

sorry for the rambling answer, just wanted to cover everything, just in case..

btw, we do tranny fluids too..

 

[76zimmer]

I appreciate your rambling....This is a THM400 in my Vette. under a 1/4 mile pass, the 2-3 shift takes ~a second. The 1-2 shift is firm and no slippage. The trans has about 50 hard passes on it, which I don't think is much for a hi-perf rebuild. the fluid has about 30 passes on it, and still looks pink, Valvoline brand. It has a 6x12 stack cooler on it, no radiator cooling.
Is a adjustable vacuum modulator any benefit here?

 

[bowtiepower00]

FWIW, in my own testing using a shop air compressor that we ran ATF in, the Trick Shift lasted a noticeable amount of time longer than the other brands I tried before it turned into milk and broke down. Napa brand was by far the worst. I tried probably 4 or 5 different brands, I'd guess. Not the most scientific, but definately a torture test for any oil, the compressor was ran hard 8+ hours a day under 90%+ humidity.

 

[dyeager535]

Modulator determines shift firmness based on engine vacuum, but if doing full throttle passes, adjustable *probably* won't make much difference since vacuum is probably nil already. You could disconnect the modulator hose and run it, race only, who cares if it's running at full line pressure.

 

[4by4bygod]

I appreciate your rambling....This is a THM400 in my Vette. under a 1/4 mile pass, the 2-3 shift takes ~a second. The 1-2 shift is firm and no slippage. The trans has about 50 hard passes on it, which I don't think is much for a hi-perf rebuild. the fluid has about 30 passes on it, and still looks pink, Valvoline brand. It has a 6x12 stack cooler on it, no radiator cooling.
Is a adjustable vacuum modulator any benefit here?

Knowing all that, I'd go back to the tranny builder, and see what he has to say..maybe the issue lies in the valve body..maybe the bands are out of adjustment? 50 passes isn't anything..

I've had "hi perf rebuilds" too, and ended up with faulty pumps that wouldn't build enough pressure to move the car, and I had one shop sell me an aluminum case TH350, that was so pourus ( from faulty casting) it would seep fluid ( passing through the walls of the casting, not a seal or gasket ) and every shift occured at 1500 rpm..

funny thing is, I spent a long time working in an aluminum casting foundry, so knew all about porosity, and knew what I was looking at when we finally put it on jackstands and watched it happen.. I wouldn't have believed it, if I wasn't familiar with the phenomenon.. the shop had just gotten a junkyard case, filled it with whatever internals, and charged me top buck.. it was "transmissions by bruce" here in cleveland, if anyone wants to know.

you just never know sometimes, what you're gonna end up with..

again, I don't think fluid is your issue.

 

[76zimmer]

thanks guys, I guess I'll give it a shot as I've already bought the stuff, and disconnect the mod. just to see if it has any relevance.