904 trans question

[FASTDARTCHESTER]

OK,

I rebuilt my 904 last summer and it was very reliable. Always hit 2nd hard and had no shifting issues. Has a B&M shift kit, 1-2 accumulator spring removed, and line pressure kicked up, and Kevlar bands. As stated, no problems until the other nite...

I had a hard run and it shifted nice and hard into second but when the upshift to drive hit, the engine slowed down and the tires locked up!!!! Keep in mind I was in drive the whole time. When i then tried to downshift into L1 (at a stop) the engine wanted to die. Reverse was slipping bigtime too.

So i got home and put it in reverse, slightly accelerated and BAM. Reverse was back. Went for a drive and all gears were back just as good as before. Tried another hard run and the same thing as above happened...


Could the Kickdown band be 'welding' to the shell on the hard 1-2 shift and holding the shell in place? I have to investigate what happens if the band gets stuck. Haven't had a chance, thought maybe someone may have experienced this.

I have rebuilt several 904's and never had this problem.

Thanks for input!

[dizuster]

Well the intermidate (2nd gear) band is definately the problem. 1st gear uses forward clutch-rear roller clutch (sprag). (in drive it doesn't use the rear band) 2nd gear uses the forward clutch and the 2nd gear band. 3rd gear is forward clutch, high gear clutch. So yes it's definately the 2nd gear band. But I would have to guess that the servo is stuck not the band. The reason I say that is if the band was stuck the plate between the 2nd gear band and the 2nd gear lever would have fallen out when the servo came off and then the 2nd gear wouldn't have worked again. Also it could be a valve body problem but I doubt that because the high gear clutch circut pressure, is also the "off" (or backside servo) pressure for the 2nd gear band. If the valve body was screwed up and the high gear clutch didn't come on/ turn 2nd gear off. The trans would be in neutral, not lock up. I would take a look at the 2nd gear servo and see if it's got something wrong with it or not. (plus you don't have to take the trans out to look at it! I had the 904 out of my duster 8 times last year looking for a 2-3 flare problem so I'm really really familiar with them. If you need any more help please ask!

Scott

Dizuster@aol.com