Toploader questions

[c9zx]

I have a RUG M3 wide ratio from a 1969 Mustang/Cougar 390 that I need to go through. Casting date on the C8 main case is 02/06/1969. I've looked on David Kee's site and have the book he sells. The question is, would this transmission have type 3 or type 4 detents and springs? Second question, are the 1 and 2, and 3 and 4 shift rails the same or slightly different? The problem I'm trying to fix is, it really doesn't want up shift into 3rd gear but will. But it will not downshift from 3rd into 2nd gear. Any input will be appreciated. Chuck

[allrightmike]

  This info may or may not be helpful. These transmissions use GL4 lube made for brass blocker rings. The synchros do not want synthetic gear lube (hard shifting).  The detent thing can be very confusing (they changed the design at least three times). Take photos as you disassemble the various pieces, keep them in order, you'll be glad you did.

[hotrodford]

It could have either 3 or 4.  The shift rails are not the same.  What do the dog teeth on 2nd and 3rd look like?  If they are worn, then the ends of the splines on the slider are most likely worn also and that greatly affects downshifting. Even if the dog teeth, on the gears, were perfect, if the ends of the splines, on the slider are worn it won't shift smoothly.

I don't like the needle bearing pilot bearings.  If that has failed 2-3 and 3-2 shifting will be unsatisfactory. I only use "bronze" pilot bushings.

I use GL5 in my 69 Mustang vintage road race car, it shifts rather good and the blocker rings are not showing abnormal wear.  What I have read about the current GL5 gear oils is that they have to be at boiling temperature to damage brass blocker rings.