1966 AT 727 repair - questions

[Frank Odenthal]

My 1966 AT 727 with a 19-spline is being overhauled. While inspecting my front clutch with four friction plates, I noticed that an additional metal plate was installed in the base of the mount. The measured clearance was 0.055" (1.4mm).
When I remove the too much metal plate, the clearance is 0.122" (3.1mm), which is within the upper tolerance limit.
The metal plates have some strange grinding pattern and looking burned in some areas. Looks like that tranny was repaired in the past already. Someone tried to smooth the metal plates but this does not look good.

Are the burnt spots on the surfaces due to the insufficient play?

I will update this clutch with 5 Read Eagle friction plates and new Kolene Steel plates anyhow.
What would be the optimal clearance for 5 friction plates ?

Thank you,
Frank

 

[413]

.055 too tight, .122 too loose. The snap rings come in different thickness to adjust clearance. Having an extra plate won't bother anything. I like to have around .080 clearance for 4 discs.

Factory spec is .024-.123, then in 1969 the spec is 056-.104 for 4 discs. Which is a better range.

Yes the clutch plates are burnt. We don't know if that is from bad driving habbits, trailer towing, or too many WOT upshifts. Or valve body problems or driving with fluid low.