Thread: Which is stronger - ZF Auto or 5 speed manual

I recall a reading a few threads that describe the ZF Auto as bulletproof. Providing it has been properly looked after, no doubt.
Sorry, not much help I'm afraid.

Both are rated to 380Nm and both will fail. The ZF can be uprated though with different parts from the 480Nm spec auto and additional coolers can be added to prevent overheating.

Negating driver technique and from a purely statistical point of view

from a gear train only perspective FOR max power through put and torque handling the ZF is stronger.

if you discount the costing of a perfect maintenance regime then again the ZF is stronger.

speaking from an overall reliability perspective the 5 speed is stronger. as it is more fault tolerant. the 5 speed will continue to provide some drive with several things out of tolerance or completely failed.

if you consider reliability to include the 50% predicted failure rate repair and maintenance costings then again the 5 speed is stronger. (this covers additional damage caused and repair costs incurred for repairing the most common fault that causes the transmission to fail to transmit drive)

to summate.

If you are going to look after it then the ZF is stronger if overall cost VS distance comes into the equation then the manual is stronger.

If you want to get to the point that you are actually worrying about it then no, neither is strong enough and you should buy a GMC Sierra with a Duramax and Allison Auto.

JC

The NA spec ZF is supposed to be better than the local ones too. (I think)

I would find a ZF4HP24EH from a 4.6V8 P38a Rangie, have it rebuilt by A&B in Melbourne or some ZF specialist and then replace your ZF4HP22EH with it. Its about 15-25mm longer but is has all of the good gear in it from the factory. I would also run an additional ATF cooler, and I would use the large torque converter for it. That setup is rated to 480Nm but will probably take a bit more if you don't abuse it due to the larger torque converter and the additional cooler and it will be a better setup than an upgraded 4HP22EH which is what you currently have.
for fitment, you will need to check and possibly modify your rear transfer case mounts slightly and check that there is enough slip in your propshafts.

Originally Posted by d@rk51d3

The NA spec ZF is supposed to be better than the local ones too. (I think)

I think the NAS market got the Disco2 with the 4.6V8 too, so they more than likely had the ZF4HP24EH auto as the 4.0V8 has the 22EH at its specifed limits.

I bet you $10 my 5th gear is stronger than your auto's fifth gear

I have a D1 auto which is a nice smooth shift and they are a good box, but I just love changing my own cogs and the acceleration of the 5 speed. I dont know which is strongest, but I do like the idea of being able to cheaply re-build mine one day.

Cheers