ZF4 Transmission cooler thoughts..

**LRJim** · 14th February 2019, 04:46 PM

Today I spontaneously bought a Davies Craig transmission cooler, it was right next to the $7 HT lead that i walked in for.... you all know how the story goes.. I know I should have bought a p38 one but like I said it was spontaneous...

After coming home and doing some research im having 2nd thoughts about it being up to the job. So I called DC and got some info on the cooler I bought, long story short its tested to run constantly at 150psi which im thinking is probably right at the safe limit. After telling him that the ZF4 runs at about 150psi at 2000rpm he was pretty shocked so he tried his hardest to get info for me, but he couldn't really find much more than that.
He told me that their transmission coolers are sourced from PWR and that PWR coolers are rated at 300psi, if thats the case i should be sweet then.

So i dunno what to think about them really..

Had anyone ever used these withought issues?
Or should I pack it up and return it?

Here is the DC one :
Davies Craig HYDRA-COOL UNIVERSAL V8 TRANS COOLER (21 Plate) - PART No: 678

And the PWR one which im struggling to find info on:
Transmission Oil Cooler kit, 280 x 200 x 19mm, 3/8" outlets | PWR Performance Products

I honestly think it will be fine, ill find out quickly if its not.
But I'd like to hear some other peoples thoughts on them.

Cheers Jim

**strangy** · 14th February 2019, 05:37 PM

Why do you want a bigger cooler?
Do you have heat problems or wanting to prevent issues not realised?

**LRJim** · 14th February 2019, 05:53 PM

Originally Posted by strangy

Why do you want a bigger cooler?
Do you have heat problems or wanting to prevent issues not realised?

Mainly because I tow alot.
Its not uncommon to fit the p38 cooler which is similar size to what I have bought, no issues with the trans and id like to keep it that way

**LRJim** · 14th February 2019, 05:57 PM

What im finding is that its max psi is in reverse and that's up the 160 mark
But im also finding that the cooler lines are much lower around 70 psi.
Im thinking its going to be fine as long as it can run in reverse...

**LRJim** · 14th February 2019, 06:07 PM

About fitting an external filter

"On top of that, Jurgen said he was advised by the ZF engineers that one should NEVER fit an external filter to this model of transmission. Upon torque converter lock up, the pressures in the cooler lines go to 60-70 psi and ZF knows of at least one case where an external filter ruptured, spilling fluid onto the exhaust and setting fire to the vehicle. So they say DON'T DO IT."

D-90 FAQ - Transmission & T-case: Auto Trans

**Pedro_The_Swift** · 15th February 2019, 06:09 AM

I have two external coolers so I'm obviously going straight to hell !!

The only concern I have is your choice of 3/8'th fittings,, the standard LR/ZF lines are 1/2", you can get PWR with 1/2" fittings and tubing,

70lbs is not really a concern unless you havent check your flex to steel gearbox connections.

**LRJim** · 15th February 2019, 03:15 PM

Originally Posted by Pedro_The_Swift

I have two external coolers so I'm obviously going straight to hell !!

The only concern I have is your choice of 3/8'th fittings,, the standard LR/ZF lines are 1/2", you can get PWR with 1/2" fittings and tubing,

70lbs is not really a concern unless you havent check your flex to steel gearbox connections.

Theres a special place reserved for people like you 🤣

Yes the 3/8 fittings are a bit of issue, found out the zf has 1/2 afterwards. I was thinking about just getting a 1/2 to 3/8 adapter but I dont know if its going to cause problems.
What type of coolers do you have and where did you fit them?
Also i dont know if i should do away with the ZF one or tun both in series...

**CU55TM Disco** · 15th February 2019, 05:05 PM

Originally Posted by LRJim

About fitting an external filter

"On top of that, Jurgen said he was advised by the ZF engineers that one should NEVER fit an external filter to this model of transmission. Upon torque converter lock up, the pressures in the cooler lines go to 60-70 psi and ZF knows of at least one case where an external filter ruptured, spilling fluid onto the exhaust and setting fire to the vehicle. So they say DON'T DO IT."

D-90 FAQ - Transmission & T-case: Auto Trans

I wonder what their thoughts are on external thermostats?

**Slunnie** · 15th February 2019, 08:29 PM

If it has push on and a hose clamp fittings then its not up to the job, if it has multibarb pirtek fittings or high pressure fittings then it will probably be ok.

I've spent a lot of time and money working this out, not to mention a lot of ATF on the road, on workshop floors workshops, on tow trucks and on my back window..

Towing, the additional cooler is the best thing you can do for it. I run mine behind the grill and in front of everything else. As soon as I got the the cooler type under control the transmission has been 100% reliable, best mod for the gearbox. My probs came from more power torque from the engine and mud in the ATF cooler in the original location.

**strangy** · 15th February 2019, 08:48 PM

Remote Mount : 40 Row Hyper-Cool Extreme Remote Cooler, -8AN

This is probably what I will fit to mine if I lash out on a bigger intercooler. Easy fit under my tray. Not so easy for wagons etc though.
Most of the things on shelves in supercheap/repco/aotobarn etc are more suited to older vehicles with nothing at all.
Like everything, you get what you pay for.

Thread: ZF4 Transmission cooler thoughts..

Thread Tools

ZF4 Transmission cooler thoughts..

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions