c6 3rd gear weak?? How to build it better???

[59megawagon]

as far as I know I have a truck VB with a Transgo manual valve body kit installed.

I also have a low first gear from a Aod and a 2.5 in. kevlar band. Oh and a "R" servo in the case.

Tom.

Frank: Have you seen this problem before? It is major wear on the forward planet. This is from less than 500 street miles. It is like a 1/16 in. groove in the steel planet.

[Dman64]

Originally Posted by Frank Merkl

changing the VB to a constant pressure vb
Frank

Or package up your VB and send it to Frank and he will make it happen.

D

[Frank Merkl]

and why would you be running a low ratio set up? they don't like over 600 hp
Frank

[59megawagon]

Originally Posted by Frank Merkl

and why would you be running a low ratio set up? they don't like over 600 hp
Frank

I thought with the weight of my car a lower first gear would be better.

P.S. I also use a 2500 stall converter.


This trans has been built by 3 different shops over the last 10 years. I have been led by the nose and told what I should do by all of them and this is what I have.... I am not a transmission builder at all but I have taken mine apart and put it back together and it still worked... I know there are guys out there like yourself that know everything there is to know about these but there are none like you in my town.

[gregaust]

Originally Posted by BOSS 429

/\ THAT MEANS NOTHING

I've probaly tried more brands of valve bodys then anyone over the years, FRANKS have been the best. 4 years ago I had 1 company send me 15 to try, drove my trans guy nuts

all junk, Go with what frank say's

Glad i;m not the only one Good ones are few + far between.

Originally Posted by 59megawagon

as far as I know I have a truck VB with a Transgo manual valve body kit installed.

.

And there could be part of the problem. The Transgo V/B is one of the few manuals that do run modulated line pressure ..

[59megawagon]

I was running this trans with no vacuum line to it and I guess that runs full line pressure all the time??? after the first failure the tranny guy said the planet was being eroded from running full line pressure all the time on the street???? Again I have no idea???? I run a vacuum line now to the trans....

Tom.

[gregaust]

Not exactly . Running the Transgo kits with no vacuum does raise line pressure , BUT from testing i have done the line pressure tends to be erratic and a bit out of control .. It does clearly state in the Transgo instructions that vacuum must be hooked up..

With the vacuum connected it could be ok BUT again you'd need to be checking it with a vacuum gauge to ensure the pressure did rise fast enough to cope with the torque load you are throwing at the trans ..
The best way IMO is as Frank said , a manual valvebody with a good constant line pressure . You will find with this type V.B the pressures should be very stable , unlike leaving the vacuum off what you currently have .

As you've probably seen here Franks valvebodies are the best available for a C6 if you can get one .

Then build the trans up as per his specs and i think your issues will go away . All Franks setup and clearances are listed in the sticky post .. They are good tested + proven specs that work with his valvebody .

I don't know that i agree that excess line pressure eroding the planets , not heard or seen that before . After the trans is built a pressure gauge is your friend , needs to be checked then you know it is right and has a chance of living .

[59megawagon]

Originally Posted by gregaust

Not exactly . Running the Transgo kits with no vacuum does raise line pressure , BUT from testing i have done the line pressure tends to be erratic and a bit out of control .. It does clearly state in the Transgo instructions that vacuum must be hooked up..

With the vacuum connected it could be ok BUT again you'd need to be checking it with a vacuum gauge to ensure the pressure did rise fast enough to cope with the torque load you are throwing at the trans ..
The best way IMO is as Frank said , a manual valvebody with a good constant line pressure . You will find with this type V.B the pressures should be very stable , unlike leaving the vacuum off what you currently have .

As you've probably seen here Franks valvebodies are the best available for a C6 if you can get one .

Then build the trans up as per his specs and i think your issues will go away . All Franks setup and clearances are listed in the sticky post .. They are good tested + proven specs that work with his valvebody .

I don't know that i agree that excess line pressure eroding the planets , not heard or seen that before . After the trans is built a pressure gauge is your friend , needs to be checked then you know it is right and has a chance of living .

Thanks for all your and franks info. I will take that into account after I get the motor running correct. I have some new fuel pump parts coming from Weldon and hope to get it on the dyno within the week???

Tom.

Here is a video of the car running.... http://www.youtube.com/watch?feature...&v=QDo96Q1gvR4