Thread: L322 AFTERMARKET TRANSMISSION COOLER INSTALLED

PWR Aluminium Radiators, Intercoolers & Oil Coolers

These guys make seriously good quality coolers but most importantly they are available with larger tube sizes, IMO this is quite important to retain the flow rate to at least the same as the factory cooler.

JC

Hi guys i just want to add some information on Transmission Oil Coolers.

Now you can have as many oil coolers as you want but at the end of the day if you restrict the flow of the oil the transmission will over heat.

The way cooling systems work on automatic transmissions is by making use of the exhausted oil left over from the pump once the Regulator valve has sent the corrected pressure to the valve body.

This left over pressure then tracks to the cooler and then back to the transmission and usually it returns to the gear sets as lubrication/Cooling. Now there is a fail safe in the system which allows oil to return to the sump if the cooler blocks or is restricted or some sort of over pressure issue as a back pressure into the pump would cause major issues.

After you fit your coolers i recommend doing a flow check as the return line of the transmission. With the help of someone have the line off the transmission and start the car in park @ idle. With a bottle at least 2 litre's or larger to catch the oil count how many seconds it takes to catch at litre 1 litre.

Recommended flow is 1 litre for 15 seconds Bad flow is 1 litre 30 seconds. (This is just a reference point i use it not a pacific ZF flow measure)

Also this fitting i make may also be suitable if you buy one and it doesn't send it back for a full refund




Cheers
Rhys

I would be getting down to Enzed or hose doctor and getting some decent hose fittings on the lines.
Utilux hose clamps are a bit under rated for such an application i feel.

Originally Posted by RR P38

I would be getting down to Enzed or hose doctor and getting some decent hose fittings on the lines.
Utilux hose clamps are a bit under rated for such an application i feel.

Yep!

My experiences (note plural) are that the ZF's specifically run very high line pressure through the lines and coolers in comparison to other transmissions. About 120psi or something like that. plain, flared etc fittings with any number of hose clamps will eventually blow apart. You need to run a cooler that will take the pressure (and flow), not just a normal ATF cooler, and you need to run proper pressure fittings like Pirtek fittings etc. After trying a few, the one that I have found to be good is the one that Davis Performance Landys sell - thats not at all to say that there are not others, but this one has been reliable.

The ZF Transmission do run hi pressure compared to other transmissions but its not so much to be really worried about if you cover all bases.

• Brass Barb fittings are no good unless its has a really good angled barb on the end with a straight shaft section.

• Clamps also need to be good quality i use Wurth clamps and never had one blow yet.

• PWR transmission coolers scan be used with out issue as they have a rough raw alloy surface which the hose grips to.
• Transmission Hose is also important as it is designed to work with ATF and also barb fittings. Push lock hose or hard wall hose will blow of a regular barb.
• Don't be scared to use one clamp with the right hose & fitting. The speedflow 411 series Barb to AN adapters have Never failed me with the ZF6HP coolers kits i make for the falcons and that is with owners mostly fitting them.

The more hose you have to push on to then allow more clamps is the start of all your problems.


FYI i am working on a new fitting which will allow the removal of the painful quick release hoses and allow you to run -8AN braided Hoes & fittings. Luckily the New Ford Territory runs the same size cooler pipe and fittings as the Rovers.



Cheers
Rhys

Originally Posted by Slunnie

Yep!

My experiences (note plural) are that the ZF's specifically run very high line pressure through the lines and coolers in comparison to other transmissions. About 120psi or something like that. plain, flared etc fittings with any number of hose clamps will eventually blow apart. You need to run a cooler that will take the pressure (and flow), not just a normal ATF cooler, and you need to run proper pressure fittings like Pirtek fittings etc. After trying a few, the one that I have found to be good is the one that Davis Performance Landys sell - thats not at all to say that there are not others, but this one has been reliable.

How does the Davis Performance Landys cooler hook up the the Rover lines & Cooler?

Is there any known reason why I could not fit the cooler(s) to a TD6?

Just wondering if anyone has done anything further on upgrading transmission coolers on the L322 TD6/GM box combo. It seems that my trannie has failed because of overheating. (see post on best place in Melb to repair auto). This is despite only towing a 900kg (loaded) trailer. A&B say that the OE unit should be more than adequate to tow my replacement off road van at 1.5 tonne, however after having one very inconvenient failure I want to make sure !
Peter