MCI 9 Allison 740 slipping/shuddering in 1rst gear... Help!

[RickB]

When accelerating from dead stop on steep inclines or on spongy ground tranny shows rebellious attitude. Fluid smells a little crispy but never changes color.
Does anyone know if 1rst and reverse share the same clutches and plates? Becuase reverse works like a charm.

Anybody ever dealt with this issue before?

Rick B

[luvrbus]

Rick this may not be your problem but several month ago I was having that same problem some people I want mention any names told me it was going to cost 8000 to fix.A guy on this board sent me a email telling how to time the drive shaft I done what he told me to do and have never had another problem His name is Bryce aka  BK      hope you have the same luck

[RickB]

Thanks for the info. Do you have any more info on how to get in touch with the guy who helped you?

BK are you out there??

[prevost82]

I doubt if you have a drive shaft timing problem, I think the trany is toast if it is slipping.
Ron

[makemineatwostroke]

RickB     what is your rpm range before the transmission engages it could be something simple like the filter at the valve body or trimmer spring broken or a bad drive line a little more info on whats going on and maybe some can help.I would download the trouble shooting guide from the Allision web site and compare the symptoms    have a good valentines day

[Busted Knuckle]

Rick this may not be your problem but several month ago I was having that same problem some people I want mention any names told me it was going to cost 8000 to fix.A guy on this board sent me a email telling how to time the drive shaft I done what he told me to do and have never had another problem His name is Bryce aka  BK      hope you have the same luck

I did? Oh yeah now I remember LOL! But seriously I do remember telling you how to make sure the driveshaft was in time. But I didn't remember the symtems we were working with!

OK well the way we always put a driveshaft in is by making sure that the yokes are lined up on each end!

But I really don't think in this case it's the driveshft being out of time. It could be a bad U-joint(s), but usually with a bad U-joint or out of time driveline it usually vibrates more than in first & reverse. Also the symtoms Rick described in his 1st post are why I didn't respond as I didn't feel I had the correct answer.
  BK 

[skipn]

Rick

"on spongy ground tranny shows rebellious attitude" great verse

As a general rule with automatic transmissions
  1 clutch pack for each speed and one clutch pack that controls forward/reverse
 
doesn't sound good.....(smells a little crispy) 

Have an oil sample done. High metal content would denote clutch problems
no metal would indicate pressure or valve issues.

FWIW
Skip

[RickB]

Good News!!! I finally built my 2x12 pine drive on stands and was able to actually get under my bus for model and serial #'s and lo and behold it was a HT 754 CRD Allison and because it had a modified shifter that only showed 4 forward gears I never knew that my bus was always starting out in 2nd which explains the lugging and shuddering. Upon closer inspection I noticed there was an extra unmarked detente that allows me to finally reach 1rst gear. Now she pulls like there's no tomorrow!!! YEEHAW! Thanks for all the suggestions and special thanks to Brian Diehl who helped me solve this riddle.