Zf6 ratings?

chris89 · May 4, 2013

Why kind of hp/tq can these transmissions hold up to and what are there for upgrades?

silverpsd_06 · May 4, 2013

Usually just a clutch. At one time someone was making billet Shafts for them. Typically the tailshaft junks the case before any internals let go. They are pretty damn tough. 3rd gear synchro had a tendency to crap out over time I know mine is pretty scratchy when trying to shift quickly

chris89 · May 4, 2013

Yeah my third gear shift has the be just right but I'm starting to get it figured out. Is there any way to prevent the tail shaft problem?

littleredstroker · May 4, 2013

chris89 said:
Yeah my third gear shift has the be just right but I'm starting to get it figured out. Is there any way to prevent the tail shaft problem?

Try not driving like a jack azz Chris...

sent while looking at a hole in my block

co04cobra · May 4, 2013

A full synthetic syncro mesh fulid helps with the shifting. Also a short throw isnt a bad upgrade. As far as power and abuse. Youll break a lot of other stuff on your truck before you break the trans. Its not a trans your're going to use drag racing either, but they are very tough.

Id spend money upgrading something else first.

chris89 · May 4, 2013

co04cobra said:
Id spend money upgrading something else first.

Upgrading what?

psduser1 · May 4, 2013

I talked to the boys at Midwest.....
In order of importance they listed:

Clutch, obviously
Auxiliary cooler- think big automatic tranny cooler
Input shaft
Dan offers a input from a 6.0 six speed, because of the bigger(roller) pilot bearing
Output shaft, which is involved if you have a 4x4

I asked him about cryo treating the shafts, and Dan seemed to think it wasn't really necessary.
I understood him to say that his personal experience involved an approx 800 hp Chevy setup???

At a little over 200k, mine shifts nicely, however it has started to howl at light load state, so I'm sure there is a bearing dying a painful death. Also, at the last fluid change I could feel a hard part in the bottom of the case. Also, a 1/4" diameter spring laying in the bottom?? No idea where that's from! But it isn't right, obviously.

I was changing trans fluid approximately once a year, and its always black, so heat is a big issue. This truck is routinely hooked to 14k, and sometimes a lot more, with only slightly higher than stock power, maybe 300 hp.

rascal · May 6, 2013

psduser1 said:
I talked to the boys at Midwest.....
In order of importance they listed:

Clutch, obviously
Auxiliary cooler- think big automatic tranny cooler
Input shaft
Dan offers a input from a 6.0 six speed, because of the bigger(roller) pilot bearing
Output shaft, which is involved if you have a 4x4

I asked him about cryo treating the shafts, and Dan seemed to think it wasn't really necessary.
I understood him to say that his personal experience involved an approx 800 hp Chevy setup???

At a little over 200k, mine shifts nicely, however it has started to howl at light load state, so I'm sure there is a bearing dying a painful death. Also, at the last fluid change I could feel a hard part in the bottom of the case. Also, a 1/4" diameter spring laying in the bottom?? No idea where that's from! But it isn't right, obviously.

I was changing trans fluid approximately once a year, and its always black, so heat is a big issue. This truck is routinely hooked to 14k, and sometimes a lot more, with only slightly higher than stock power, maybe 300 hp.