928 S4 Manual Transmission Questions.
#16
Burning Brakes
The 928 Manual gearbox is made by GETRAG. Hence the G in the type name in the gearbox modeltype.
This goes for all the Porsche models, when you see a G in the gearbox description, its a GETRAG. Getrag also made the racing gearboxes for most Porsches. (The also make gearboxes for Mercedes, and BMW etc..etc..)
The rear locking diffs are ZF.
This goes for all the Porsche models, when you see a G in the gearbox description, its a GETRAG. Getrag also made the racing gearboxes for most Porsches. (The also make gearboxes for Mercedes, and BMW etc..etc..)
The rear locking diffs are ZF.
#17
Rennlist Member
The 928 Manual gearbox is made by GETRAG. Hence the G in the type name in the gearbox modeltype.
This goes for all the Porsche models, when you see a G in the gearbox description, its a GETRAG. Getrag also made the racing gearboxes for most Porsches. (The also make gearboxes for Mercedes, and BMW etc..etc..)
The rear locking diffs are ZF.
This goes for all the Porsche models, when you see a G in the gearbox description, its a GETRAG. Getrag also made the racing gearboxes for most Porsches. (The also make gearboxes for Mercedes, and BMW etc..etc..)
The rear locking diffs are ZF.
#18
Burning Brakes
Thanks for the language lesseon. Im fluent in German.
For the other Porsches, i.e 911, when it was a Porsche gearbox they used the Porsche projectnumbers, 901, 915 etc..etc.. as soon as they changed to the ''much better'' Getrag gearbox for the 911 for the 87 model year, the gearbox got a G ''prefix''. Thought this was for the 928 as well.
The Borg Warner syncros were added for the 85' model year strengthened gearbox, earlier it was the Porsche syncros.
For the other Porsches, i.e 911, when it was a Porsche gearbox they used the Porsche projectnumbers, 901, 915 etc..etc.. as soon as they changed to the ''much better'' Getrag gearbox for the 911 for the 87 model year, the gearbox got a G ''prefix''. Thought this was for the 928 as well.
The Borg Warner syncros were added for the 85' model year strengthened gearbox, earlier it was the Porsche syncros.
#19
Instructor
The torque of the rear driveshaft coupling in the torque tube must be checked each year.If it loosens to the point of allowing play (as it will, over time), you will break the transmission input shaft. Red dust (rust) around the rear coupling is a sign that there is play and that you are living on borrowed time unless you retorque the bolt (best to replace it).
Other than that, the manuals, including the diff, are built like a truck transmission. You do not need to worry about yours.
Other than that, the manuals, including the diff, are built like a truck transmission. You do not need to worry about yours.
#20
928 Collector
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Thanks for the language lesseon. Im fluent in German.
For the other Porsches, i.e 911, when it was a Porsche gearbox they used the Porsche projectnumbers, 901, 915 etc..etc.. as soon as they changed to the ''much better'' Getrag gearbox for the 911 for the 87 model year, the gearbox got a G ''prefix''. Thought this was for the 928 as well.
The Borg Warner syncros were added for the 85' model year strengthened gearbox, earlier it was the Porsche syncros.
For the other Porsches, i.e 911, when it was a Porsche gearbox they used the Porsche projectnumbers, 901, 915 etc..etc.. as soon as they changed to the ''much better'' Getrag gearbox for the 911 for the 87 model year, the gearbox got a G ''prefix''. Thought this was for the 928 as well.
The Borg Warner syncros were added for the 85' model year strengthened gearbox, earlier it was the Porsche syncros.
#21
Rest in Peace
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#23
Rest in Peace
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#25
Former Vendor
[QUOTE=Glenn Evans;9015793]The torque of the rear driveshaft coupling in the torque tube must be checked each year.If it loosens to the point of allowing play (as it will, over time), you will break the transmission input shaft. Red dust (rust) around the rear coupling is a sign that there is play and that you are living on borrowed time unless you retorque the bolt (best to replace it).QUOTE]
Exactly.
The other very common problem for 5th gears is that people crack/break them when they remove the transmissions. Even a little "side" movement, when the gearbox is removed from the torque tube can/will damage the gear.
I always suggest that people remove the coupler bolt, but leave the actual coupler in place. This will add some support to the three separate "leaf" pieces of 5th gear, as the gearbox is removed.
Exactly.
The other very common problem for 5th gears is that people crack/break them when they remove the transmissions. Even a little "side" movement, when the gearbox is removed from the torque tube can/will damage the gear.
I always suggest that people remove the coupler bolt, but leave the actual coupler in place. This will add some support to the three separate "leaf" pieces of 5th gear, as the gearbox is removed.
#26
Banned
The other very common problem for 5th gears is that people crack/break them when they remove the transmissions. Even a little "side" movement, when the gearbox is removed from the torque tube can/will damage the gear.
I always suggest that people remove the coupler bolt, but leave the actual coupler in place. This will add some support to the three separate "leaf" pieces of 5th gear, as the gearbox is removed.
I always suggest that people remove the coupler bolt, but leave the actual coupler in place. This will add some support to the three separate "leaf" pieces of 5th gear, as the gearbox is removed.
Thanks, Denny
#28
Race Director
Seriously............how many HIGH hp 928's blow manuals....pretty much ALL OF THEM.... Here is a ?? Name 1 race 928 with STOCK or better HP that completes a full season (12 on track hours) on the same trans................................................................... ........................................................................ ........................................................................ ...
exactly...not even the mighty KIBORT can claim that.....his blew up last year....Anderson breaks them on a regular basis...same for Simard..
leave it stockish...the clutch fails....upgrade the clutch the trans fails
How many ORR cars run automatics with ZERO issues...even with boost....George and Bill have done it for YEARS with no issues....
I have 85.5 hours on track on a rogerbox....that was USED to start with...17 hours in 3 days a few weeks ago... I just changed the trans fluid and filter....and after looking at it + smelling it...it really was a WASTE...still red fluid and no burnt smell at all....I had a YEAR (40 HOURS) of track time on that fluid-filter (normal fluid, nothing special)....however I NEVER-EVER see more than 180F on my trans temps either...a good cooler helps
It really is the "poor mans sequential" for minimal cost....
Okay stepping off the soapbox with flame suit on
#29
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Colin
If you can design it I can probably build it. I would be interested in helping if you decide to move foward.
I have the Widows old box here. Maybe I should open it up and look inside.
If you can design it I can probably build it. I would be interested in helping if you decide to move foward.
I have the Widows old box here. Maybe I should open it up and look inside.
#30
Rennlist Member
+1 on what GregBBRD said re leaving the coupler in place to support the relatively weak (for angular movement) end.