engine braking
Viala
03-05-2005, 06:34 AM
hello,
I would like to know about engine braking on a transport 3.8.
I thought it was a transmission failure when I bought the car in 1999 After a big breakdown I changed the transmission last week , but it is always the same I don't fell the engine braking like on a manual gearbox, may be it is normal on an automatic transaxle.
The transmission shift correctly, on gear 1 or 2 I feel the engine braking
but not on D or overdrive
thank's for your answer
Paul
I would like to know about engine braking on a transport 3.8.
I thought it was a transmission failure when I bought the car in 1999 After a big breakdown I changed the transmission last week , but it is always the same I don't fell the engine braking like on a manual gearbox, may be it is normal on an automatic transaxle.
The transmission shift correctly, on gear 1 or 2 I feel the engine braking
but not on D or overdrive
thank's for your answer
Paul
LMP
03-05-2005, 09:23 AM
THis is OK Paul. The 1-2 band applies in 1st and 2nd selected ranges and does not apply in D or OD ranges.
www.avigex.ca/xport/transmissionranges.jpg
This is the virtue of the Hydramatic that makes for its shooth shifting without elaborate synchronisation schemes: contrary to other transmissions, up shifting only means applying one more disk clutch for each consecutive gear without having to release a band in synchronism (which makes hard or lousy shifting on other makes). THis is accomplished through additional use of one way sprag/roller clutches...Conversely, downshifting just releases disk clutches one after another. However, this equates to one-way free wheeling in 2 and 1st gear when decelerating (in D or OD ranges when engine runs slower than the car). Anyway, when decelerating in D or OD, autoshift to 1st would happen only at a very slow speed thus to no real use for braking.
When selecting 2 or 1 , the 1-2 band applies and does procure engine braking as you mentioned.
www.avigex.ca/xport/transmissionranges.jpg
This is the virtue of the Hydramatic that makes for its shooth shifting without elaborate synchronisation schemes: contrary to other transmissions, up shifting only means applying one more disk clutch for each consecutive gear without having to release a band in synchronism (which makes hard or lousy shifting on other makes). THis is accomplished through additional use of one way sprag/roller clutches...Conversely, downshifting just releases disk clutches one after another. However, this equates to one-way free wheeling in 2 and 1st gear when decelerating (in D or OD ranges when engine runs slower than the car). Anyway, when decelerating in D or OD, autoshift to 1st would happen only at a very slow speed thus to no real use for braking.
When selecting 2 or 1 , the 1-2 band applies and does procure engine braking as you mentioned.
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