[Big86inthestixx]

I have got a Th350 trans... and i have been told that if you put type F Trans fluid in it, it usually makes it shift a little harder. But i need to know is if i change my trans fluid, how do i get the trans fluid out of the torque converter, if not can i mix a little Type F and dexcron mercron?

[DoubleVision]

there is no way really to get the fluid out of the converter without removal. it`s okay to fill up and run Type F, I`ve did it for years with several tranny`s and never had a problem. I never noticed it shifted any harder, but it`s what was recommended with my converters by B&M

[willys36@aol.com]

My old 1954 hydro had a drain plug in the fluid coupling can so I can do a complete fluid change. Modern torque converters don't. The two fluid systems THEORETICALLY take different approaches to provide soft shifts for Ma and Pa. GM's approach is to drill large orifices and use Dexron fluid which has the property to get 'slipperier' as clutch speed slows down on engagement down to soften shifts. Ford on the other hand drills small orifices and uses type F fluid which gets "stickier" as the clutches slow down but get soft shifts due the the orifice restrictions. Thus if you use type F in a GM tranny, the large orifices and sticky fluid should result in quicker clutch apply and less slippage. In fact, B&M's SlickShift is basically Type F fluid with some magic elixir additions and a different dye color. Use Dexron in a Ford, on the other hand, and the slick fluid and small orifices supposedly results in exaggerated clutch slippage and quick demolition of the tranny.

We had this conversation on this board last year and 4 Jaw Chuck commented that he used to work for a company that formulated both Dexron and Type F fluids and all they did was take the same hydraulic fluid base, dye it to meet the buyers color preference and put the same exact fluid in every can. Food for thought.

[Big86inthestixx]

thanx alot you guys i think that i will just drain it, fill her up with some type f. run it for a while then change it again in a month er so and re fill it with type f...

P.s. Willys, are you saying that basically i can use any hydraulic fluid... if so which do you prefer...?

[willys36@aol.com]

4-Jaw is the pessimist. I am the eternal optimist and run Type F, believing it is better for my rod than Dexron.

[Big86inthestixx]

Ok... i have a full manual valve body... in my offroader. and i want to make it shift harder, and have firmer shifts... which will do that better.. i am guessing type F...also do you know any other ways to make my Turbo350 shift any harder..

[willys36@aol.com]

If the fluids truly function as designed and 4-Jaw is wrong (fat chance), Type F is the best choice for any transmission. In theory, it should give quicker clutch engagement in GM trannys.

[11secmudtrk]

Type F will make it shift harder, I run it in my manual valve body th400, and it'll spin all four 38.5s when it hits 2nd.

[Big86inthestixx]

well thank you guys alot for all of your info...i am definitly going to put some type f in my trans.... but i would still like to know how to make 1-2 hit harder, maybe 2-3 also...thanx alot...

[poncho62]

You can buy a decent shift kit for under $100, which when installed will really wake up your tranny. You can, if you are careful, install it yourself. Just follow the instuctions, to the letter. A tranny shop will probably install it quite cheaply, if you are not sure of yourself.

[11secmudtrk]

He said he was running a manual valve body...there isn't much that will make it shift harder without going into the trans.

[poncho62]

My mistake.......

One would think. If you have a manual valve body in a tranny, you would also have a shift kit, amounst other stuff, and it would be hitting pretty hard as is. Unless something is slipping in there to make it "slushy"

Just my thoughts.....I may be wrong. I was ONCE before.

[M&M CUSTOM]

If it's such a beneficial move to go with type F in a GM tranny, can someone tell me if they have had this in theirs for a few years' time, if they have realistically seen any long term benefits and differences than with Dextron II?

I am now curious, as I have an empty rebuilt TH-400 in the shop.

[11secmudtrk]

With a manual valve body the springs, balls, and modulator are removed, basically the essentials of a shift kit, so yes you may be wrong again.



Reason for edit: keeping it peaceful around here.

[Crosley]

Depending on the guy who built the tranny there may or may-not be accumilator springs in the tranny.

Some check balls are required in the forward shift pattern FULL manual valve body.

in a reverse shift pattern vb the check balls usually are all removed.

I have used Dexron fluid for decades.

Type F has fewer friction modifiers in it. Some folks think the Ford fluid provides firmer shifts.

This is a discussion that has been going for years.