How much can a ZF5 (S5-42) handle?

[Buffalo444]

How much can one of these handle power wise? I'm debating on putting it in my current truck (rusty pos OBS) or waiting until I get another super duty. I'm wondering how the 4.14 first gear will fair towing with 4.10s too...

 

[Charles]

In my experience, they will handle pretty well all the power you can practically make in short bursts. Some people have broken them bouncing down the track, but on smooth roads, they shouldn't break.

For continuous duty, in my experience, they will not hold 300rwhp without overheating, leading to eventual failure popping out of gear. I now have a cooler on the one in my 550 in addition to the one in the radiator, which seems to be helping. I'll know more next oil change, as to whether the fluid is scorched again.

As for the clutch..... good luck. A clutch that will hold much over 500rwhp isn't going to be DD friendly, unless new syncros are considered normal for an oilchange, or you don't mind shifting it like a 9 speed fuller.

 

[JCart]

Hey Charles,

Any pix or write up on how you did your cooler install? What did you use for a pump and suggested gallons per hour? What would be a normal op temp for the ZF? Reason I ask is I swapped out my E4OD and left the v10 cooler in the front bumper and the tranny temp gauge in the pod to, so just looking for ideas as it's on the list of too does.
Thanks
Jrc

 

[Charles]

Hey Charles,

Any pix or write up on how you did your cooler install? What did you use for a pump and suggested gallons per hour? What would be a normal op temp for the ZF? Reason I ask is I swapped out my E4OD and left the v10 cooler in the front bumper and the tranny temp gauge in the pod to, so just looking for ideas as it's on the list of too does.
Thanks
Jrc

The ZF has a factory pump. At least all my ZF6 speeds did, that runs through hardlines just like the Auto pieces up to the lower portion of the radiator through a liquid:liquid exchanger.

I simply cut the hardline heading back toward the trans and ran an inline cooler with the factory unit in the radiator. That way the factory unit can keep the temps up in the winter, and take the brunt of the hit when towing, and the additional air:air unit can knock the temp on down with ambient air when towing hard, and the engine coolant itself is getting too warm to offer the trans fluid much delta.

For a superduty, the line leaving the driver's side of the radiator is the return line where you would want to tie-in.

My tie-in:

And I just used a 49 dollar cooler from Advanced. I didn't feel the need to pay nearly 200 dollars for a Ford unit, although one would have been nice.

Mounted it like so:

Mentioning E40D, makes me think OBS? And if you've already swapped to the ZF5 and driven around, I take it that means there is no factory internal pump...

In which case I wouldn't worry about it. I would swap to a ZF6 before I dicked with that.

 

[Buffalo444]

yeah this is an OBS trans, the early 5 spd. I'll probably stick it in this or a mostly stock super duty i guess.

 

[JCart]

Thanks Charles... Sorry mine's an OBS and I swapped in the ZF-5, thanks for the info though will be good for the SD guys. Too funny because when I read your initial post thought you where speaking about the ZF-5 and not the 6....thus the pump and gph info... Hahaha

jrc

 

[Patrick Feeley]

You can put an external pump on the ZF-5, but it won't be a cheap endevour! I thought about it on my 94. You will need to modify the PTO covers for inlet/outlet ports (or find a couple of Fabcraft Metalworks billet covers that have the ports), get a pump (Weldon 9200-A, Tilton 40-525, or Mocal 17-522HT ... $200-$400, get one with Viton seals), Temperature Switch (don't want to pump when its below temp), Cooler, and of course all the fittings and lines. The pumps are usually around 0.5-2.0 GPM. Cheers!

 

[JCart]

You can put an external pump on the ZF-5, but it won't be a cheap endevour! I thought about it on my 94. You will need to modify the PTO covers for inlet/outlet ports (or find a couple of Fabcraft Metalworks billet covers that have the ports), get a pump (Weldon 9200-A, Tilton 40-525, or Mocal 17-522HT ... $200-$400, get one with Viton seals), Temperature Switch (don't want to pump when its below temp), Cooler, and of course all the fittings and lines. The pumps are usually around 0.5-2.0 GPM. Cheers!

Thanx Patrick,

What temp do you think the ZF-5 would get under normal summer 70 F to 105F temps pulling loads to say 10,000 lbs? Still have my E4OD gauge in the pod and was wondering if a guys would need one that shows hotter than 250 F?

This is on the to do albeit a ways down the list...

jrc

 

[Patrick Feeley]

I had a gauge on the 94. It would get up to 240-250F in 4th and 5th on a good hill climb (Eastern Sierra in summer) with the fifthwheel in tow. It takes awhile to come down too, but it does. IIRC it would run 190F-ish or less unloaded cruising. Cheers!

 

[JCart]

Thanks Patrick