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Technical => Dan Dishon's Transmission Den => Topic started by: spookie on May 25, 2015, 04:46:41 AM

Title: transbrake not holding
Post by: spookie on May 25, 2015, 04:46:41 AM
Had PG trans rebuilt and transbrake would not hold at all.I have taken it apart and tighten rear clutch pack. {.082} Brake holds to 3500 rpm then will roll.Rebuilder used B&M clutches,good or bad?? Trans worked fine but for transbrake. My 1500lbs F.E.D. runs 5.60 in 1/8  8.80 in 1/4 so not much power. Checked press at servo 220psi.Need a little help!
Title: Re: transbrake not holding
Post by: bikeguy307 on May 25, 2015, 11:08:15 AM
Sounds like the solenoid is not holding, or possibly the valve is not getting set in deep enough. I have seen a worn valve cause the same the problem. These are some things to check, also not sure what brand valvebody you are using but most all like a .050 to .070 clearance on the reverse clutch. Keep in mind I do not think the clearance is your problem.

Hope this help
Dan
Title: Re: transbrake not holding
Post by: masracingtd1167 on May 25, 2015, 02:46:55 PM
Had PG trans rebuilt and transbrake would not hold at all.I have taken it apart and tighten rear clutch pack. {.082} Brake holds to 3500 rpm then will roll.Rebuilder used B&M clutches,good or bad?? Trans worked fine but for transbrake. My 1500lbs F.E.D. runs 5.60 in 1/8  8.80 in 1/4 so not much power. Checked press at servo 220psi.Need a little help!
    Did the trans brake work before it was re built ? did the guy who re built it take the trans brake apart ? Some use a check ball some don't Some use special gaskets some don't ! I screwed one up once !It seems like every manufacturer makes theirs a little different i'm sure that Dan would agree .We had a solenoid fail on my sons car and it did the same thing . 
Title: Re: transbrake not holding
Post by: bikeguy307 on May 25, 2015, 05:09:13 PM
It very well could be a gasket problem, leaking just enough to not hold solid. If the ball was missing it would apply the brake in rev. the ball is so it doesn't back feed low when in reverse on pro tree valvebodies.