Posts: 368
Threads: 28
Joined: Aug 2017
Our '86 has an Allison four speed with Stone Bennett shifter , hydraulically activated. Started having an intermittent problem shifting from neutral to drive during a 700 mile trip Friday . Twice it also would not go into neutral from drive , so I had to manually move the lever at the trans . Problem seemed to worsen as the day got hotter .
I can't see anything obvious at the trans shifter station , and the toggle shows voltage on outputs when moved forward and back . The shifter has an accumulator which has a Schrader valve on it . I am wondering if this should have air pressure . It seems like it should , but I want to be sure before trying to add air . Trans shifts fine , no slippage .
Anyone have any info on these shifters ?
Thanks , Chris
1986 #89
VIN 007
Detroit 8V92 TA 475 HP
Allison four speed
Chris and Sharon Hand
Posts: 5,853
Threads: 500
Joined: Jul 2012
if you do a search on the forum you will find info about it. btw, it is air operated and not hydraulic.
quite a few gurus have worked on them. there is a place in texas that rebuilds them as well.
tom
2014 Haulmark 40' Super C on Freightliner Cascadia ISX15 Easton 13 speed
Former Owner 1990 38' Newell Coach 236 8V92
Former Owner 1999 45'8" Newell Coach 526 Series 60
Former Owner 2002 45'8" Newell Coach 608 Series 60
Posts: 368
Threads: 28
Joined: Aug 2017
Actually there is no air going to the shifter . There is a line from the trans to the shifter via the accumulator, and another back to the sump . Tim kindly sent a manual that covers this particular shifter including the accumulator pressure , 90 psi . So far today the shifter is working , 500 or so miles to go , hopefully we can get to the barn as is . We have nitrogen in the trailer , I can fill accumulator if needed .
Thanks for the response ,
Chris
1986 #89
VIN 007
Detroit 8V92 TA 475 HP
Allison four speed
Chris and Sharon Hand
Posts: 1,820
Threads: 130
Joined: Aug 2012
I had T H Anderson Pump Co. , Kilgore, TX Rebuild my Stone-Bennett shifter . They were great! 800-594-7867.
1993 Newell (316) 45' 8V92,towing an Imperial open trailer or RnR custom built enclosed trailer. FMCA#232958 '67 Airstream Overlander 27' '67GTO,'76TransAm,'52Chevy panel, 2000 Corvette "Lingenfelter"modified, '23 Grand Cherokee.
Posts: 275
Threads: 10
Joined: May 2015
T. Anderson was so amazing! The man KNOWS these shifters. He was real nice & fun to talk to. He explained the process of rebuilding it myself & encouraged me to do it.
All things considered, the prices were very fair.
Good luck with your shifter!
1987 classic #159
8V92 MUI , Allison 740
(This post was last modified: 07-15-2019, 05:31 PM by
kyleb.)
Posts: 368
Threads: 28
Joined: Aug 2017
Shifter update , checked trans fluid level yesterday morning. To my dismay and embarrassment the fluid was just touching the stick . Three qts ATF brought the level into the safe range . There were no shifting problems during the 700 mile trip home . I should note that the trans always shifts/pulls well , the shifter is actually a gear selector . When we had problems Friday ( mostly the N to D shift ) it was very hot and we got stuck for hours in a traffic snarl on I 65 N at E Town ,Ky . Perhaps heat soak compromised fluid pressure to shifter . We were also experiencing an overheating problem, about which I will post another thread .
I have found T. Anderson to be a very good outfit . Sourced information and parts from them when I went through the gear position indicator components .
Thanks for the input !
Chris
1986 #89
VIN 007
Detroit 8V92 TA 475 HP
Allison four speed
Chris and Sharon Hand
