Weakest part of a transmission
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Weakest part of a transmission
Does anyone know what the weakest part of a ZF 85A?
They are rated at 671HP @4500 rpm. Will they hold up at 650 to 700HP at 5500? If I understand the weakness maybe I could make some changes. The only reason I want to use these is because you can run in forward or reverse so you can counter rotate your drives and get a drop that is needed to run Arneson drives.
I did notice that the max TQ was 800LBS
They are rated at 671HP @4500 rpm. Will they hold up at 650 to 700HP at 5500? If I understand the weakness maybe I could make some changes. The only reason I want to use these is because you can run in forward or reverse so you can counter rotate your drives and get a drop that is needed to run Arneson drives.
I did notice that the max TQ was 800LBS
Last edited by ken sampson; 02-26-2010 at 01:22 PM.
#2
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We've used them up there. There was a high speed pump option at one time.
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#5
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Good trans. overall, the only problem weve seen is the 3 sealing rings on input shaft cutting into the alum. pump housing and dropping pressure, but only in commercial applications.Does not tolerate fast shifting though, a couple of times of that and you got a slipped/warped clutch module.
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Merc bell housings are "GM" engine pattern w/ bolt pattern for Velvet drive/ZF 45/63/63V trans. A ZF 85A will bolt to Merc bell housing but will need a spacer between trans. and bell housing,the input shaft is longer. Can get SAE 1-5 housings w/ Velvet Drive/ZF pattern usually for diesel/industrial apps.Will fit dual bell housing w/ spacer for longer input shaft.