Park to Reverse hard shift 80e
#1
Park to Reverse hard shift 80e
I cant figure this one out, fresh rebuilt 80e, pi stall. It will shift very hard from park to reverse if I dont let the truck idle for at least 20 seconds. If I let it sit for a minute the shift will be normal, and if I have been driving around a while, put it in park, then back to reverse its fine. Only on the initial startup does it shift hard. Ive checked the fluid at least 4 times on different occasions at different temperatures and its perfect
#5
TECH Resident
Join Date: Dec 2006
Location: Enid, OK
Posts: 870
Likes: 0
Received 0 Likes
on
0 Posts
How hard does it actually hit? If you've ever felt how hard an Allison goes into reverse when cold, take that times about five and that will get you in the neighborhood of how hard mine hits on a cold "garage" shift to reverse. Like said the cold start high idle doesn't help things any. Once warmed up mine still hits reverse pretty hard but the converter is really really tight too.
#6
Umm, pretty hard, enough for me to worry about it.
Going from park to drive is not a problem, just from park to reverse... I am not familiar with the park to reverse shift mechanism on the 80e, so im not sure if there is anything fragile in there that historically has problems...
Going from park to drive is not a problem, just from park to reverse... I am not familiar with the park to reverse shift mechanism on the 80e, so im not sure if there is anything fragile in there that historically has problems...
Trending Topics
#9
Moderator
iTrader: (1)
I've seen some issues here. The obvious is just as stated that the idle is higher when the truck is first started and so is the line pressure because of this. Another thing to address is the rear band circuit. An orifice can be installed into the case for the feed for the band. This will help slow down the apply oil for the low band so it does not apply hard. Another thing to look at is the cushion for the Hi/reverse drum. If it has been removed or the inner lip seal has been removed I feel that a harder apply will be felt. This one is kind of a double edged sword. When the trans shift to third normally a builder is going to want the most holding power by eliminating these things. However the apply in reverse is effect from this mod. I would say what you are feeling is normal. If your truck is lifted or you have a good amount of drive line slop, this condition will be more noticeable. HTH Vince
#10
TECH Resident
Join Date: Dec 2006
Location: Enid, OK
Posts: 870
Likes: 0
Received 0 Likes
on
0 Posts
Umm, pretty hard, enough for me to worry about it.
Going from park to drive is not a problem, just from park to reverse... I am not familiar with the park to reverse shift mechanism on the 80e, so im not sure if there is anything fragile in there that historically has problems...
Going from park to drive is not a problem, just from park to reverse... I am not familiar with the park to reverse shift mechanism on the 80e, so im not sure if there is anything fragile in there that historically has problems...