New Clutch Slipping
 

I just replaced the clutch disc, pressure plate and throw out bearing on my 1932 Ford pick up and it still slips at higher speeds when accelerating. I'm running a stock 1940 Flathead and a Borg Warner T5 five speed. The adapter came from Speedway Motors. I've tried adjusting the clutch but it doesn't help. Everything is dry. I've worked on and built a lot of cars over the years but this kind of has me stumped. If anyone has any ideas I'd really appreciate it.

Re: New Clutch Slipping
 

I would assume that if it is slipping at higher rpms that the pressure plate is not clamping the disk with enough pressure for it to hold. If so you would need to figure out why, clutch disk thickness? Pressure plate springs? Etc.

Re: New Clutch Slipping
 

Is it a 9" clutch? How big?

Re: New Clutch Slipping
 

i think 40 would still be a 9" with the blob

Re: New Clutch Slipping
 

You're probably right, but with a '40 engine in a '32 pickup using a T5, it's probably not a good idea to assume anything.

Re: New Clutch Slipping
 

very true

Re: New Clutch Slipping
 

How thick is the disc that was used
What flywheel was used-- the 32 flywheel uses about the same clutch as model A

Re: New Clutch Slipping
 

It's a 9" clutch pressure plate for a '40 Ford and a pressure plate with the T5 splines. The disc seems to be the same thickness as the original one that came with the T5 adaptor kit from Speedway. The engine has never been rebuilt so its original 85hp which is somewhat less now days, isn't overpowering anything I shouldn't think. All the parts are new.
Thanks guys.

Re: New Clutch Slipping
 

The flywheel is '40 Ford

Re: New Clutch Slipping
 

Did you have the flywheel refaced or did you rough it up with sandpaper?

Re: New Clutch Slipping
 

Did the sandpaper thing

Re: New Clutch Slipping
 

Im not familiar with t5 set-up,but I run a 9" in my 37 panel . Stock 8BA 3 speed Trans. Walt Dupon
t suggested running the 9" with heavy duty springs. I've had it in for 3 years with no slipping problem. Call Ft Wayne Clutch. Talk to Kerry he is familiar with this setup. I forgot to add the first 9" stock clutch did start slipping, when I ordered it I forgot to mention beefing up the springs. The truck had an 11" set-up. "Walt's words were get rid of the 11", its added weight. " It's all about horsepower" Good Luck

Re: New Clutch Slipping
 

How much free play?? Were all 3 fingers at the same height??
Paul in CT

Re: New Clutch Slipping
 

If it’s still assembled make sure linkage is clean @ pivot points & check ur linkage for any slight bends that might bind. Small bit of grease on pivot points. When I assemble my ‘35 I had similar issue & turned out a bent part of linkage binding. Straitened, cleaned, & lubed resolved. Worth a check before disassembly for other issues.

Re: New Clutch Slipping
 

Not sure if this could cause your issue but a friend of mine (who owns a machine shop) bought a Speedway adapter for a GM 4 speed and because he is a machinist, he checks everything and the machining on the opening for the transmission was off by quite a bit and he had to adjust it. If you take it apart I would check all important measurements and angles, maybe the mounting surface isn't exactly 90 degrees to the CL of the trans.
However I would measure your disk thickness with a micrometer and compare it to a stock Ford disk. I believe the difference between engaged and disengaged is only something like .050 movement on the pressure plate and if the non Ford disk is just a few thousands thinner it could be the problem too. Good luck.

Re: New Clutch Slipping
 

Hydraulic clutch?

Re: New Clutch Slipping
 

Is it slipping in all gears or just 5th. Maybe a borderline pressure plate that is not doing well with the extra load. You did properly tighten the pressure plate bolts, right? If you take it apart I would start with snugging up the pressure plate until it just holds the pressur plate and then measure distance from the plate to flywheel to get an idea how much it is compressing. If you have an extra clutch and flywheel maybe you can measure the torque required to tighten the pressure plate to compare spring tension. If there is a truck clutch and brake place near you maybe they can help you determine spring pressure.

Re: New Clutch Slipping
 

what is your rear end gearing if it,s high when your in fith it,s even higher.if all clerance checks out send pressure plate to fort wayne clutch have them increase spring pressure

Re: New Clutch Slipping
 

Good question from Richard crow. A 9" clutch with an overdrive trans with tall gears would be pretty much guaranteed to slip a 9" clutch in high gear. Besides the rear end ratio, how tall are your rear tires?

Re: New Clutch Slipping
 

Thanks guys this gives me a few things to check out for sure. The rear end is out of a '40 Ford and has 4.?:1 gears in it. I bought it that way and never had it opened up to check exact ratio. The trans has 28% overdrive. I'll check the concentricty of the adaptor to the crankshaft pilot bushing. I'll recheck my mechanical clutch linkage as well. The free play on the pedal is good.
Vern.