Jump to content

ZF4HP22 gearbox oil cooler


Ben Jordan

Recommended Posts

On my 3.9 Auto RRC I have the "Bog brush" type oil cooler for the ZF4HP22 gearbox. I am thinking of changing it to the Discovery type gearbox oil cooler that is a 4 or 5 row cooler about the same width as the radiator.

Would this be a straight swap? Or how much work is involved in swapping them over? Would it be better to change the "bog brush cooler" to something else for the same effort/money that is more efficient?

Thanks Ben.

Link to comment
Share on other sites

When off roading i can feel the heat coming through the transmission tunnel. The oil temp should be 90-100 degrees. If land rover have made a more efficient oil cooler for the Disco i would think there was a reason for it. i suppose i would know more if i fitted a temp gauge.

Link to comment
Share on other sites

It might be worth mentioning that those clamps (14,15,16) that are supposed to hold the pipes securely, don't do that job at all well. The weak fitting means that the pipes vibrate against the metal causing a crack in the pipe. The same as with power steering pipes on Disco, 90, 110 where they cross the inner face of the front crossmember.

Les. :)

Link to comment
Share on other sites

The heat through the tunnel is mostly off the exhaust on a V8. When I converted my Disco to an auto I took it for a run without the tunnel covers on and within 2 min of leaving the garage there was this blast of hot air coming up through the hole - but it was from the exhausts not the gearbox, the gearbox hadn't even warmed up.

Link to comment
Share on other sites

i've got a spare one of the disco oil cooler, tell me if you want it. had the same problem of auto trans being to hot, installed a 34 row mocal cooler. was told that the bigger the better, as well as that you can't overcool a autobox. changed the oil flow as well, oil is now only running through the mocal cooler, removed the flow through the water cooler. perfekt now, oil newer gets hotter than 90 degrees coming out of the box, and thats when heavy off roading.

got another 34 row with thermostat for the engine, perfect setup for me, engine oil temp sticks to 80 - 90 degrees, whatever i do. used to go up to 120 when pushing it hard.

since the oil first runs through the oil cooler and then through the water cooler, the cheapest improvement would be to remove the flow through the water cooler and see whether that makes a difference. is only one hose from the local hydraulic shop. as fa as i see it, that will only ensure that the oil will reenter the box being at least 80 degrees hot. not mutch cooling effect there

with regards to exhaust temp, i fitted exhaust wrap, cheapest measure to get engine bay temp down, very advisable. (and i can now hear my girl friend talk to me on the motorway, not shure what to think of that effect though B) )

Link to comment
Share on other sites

why ?

wots the prob ?

the BB cooler does a good job, change the oil regularly and filter for best results as old oil breaks down and cooling and protection is impaired

You have to be giving the GB some real stick, and or big horsepower to exceed the coling capabilities, although this shouldn't be confused with mechanical dmage which this box can sustain irrespectuive of the oil / coolers etc fited.

For upgrades etc speak to Dave at ashcroft, what he doesn't know about these boxes could be written on the back of my ear with space left over

Nige

Link to comment
Share on other sites

If you want a realy top notch oil cooler then you can not beat a "Laminova" type Water to oil cooler,

No getting bunged up with mud etc and much easier to place as you can put it just about anywhere.

Look on www.devon4x4.com for pics etc.

I have a similar one on mine and it works a treat.

Lara.

Link to comment
Share on other sites

If you want a realy top notch oil cooler then you can not beat a "Laminova" type Water to oil cooler,

No getting bunged up with mud etc and much easier to place as you can put it just about anywhere.

Look on www.devon4x4.com for pics etc.

I have a similar one on mine and it works a treat.

Lara.

Lara, We have spoke about them on the Devon forum. Too much cash for me at the moment. I think thats the thread that has got me thinking about the gearbox oil temp.

Link to comment
Share on other sites

Orange rover, Any luck with those photos?

there you go

43966.jpg

43967.jpg

43968.jpg

43969.jpg

there are two mocal 35 row 235mm units, one for the engine and one for the gearbox. they are mounted so that the connections are facing sidewards. the engine oil cooler is connected through a thermostat in the oil pump base, the gearbox cooler is always cooling. oil flow is such that the oil is entering on the bottom of the cooler.

regards

orange

Link to comment
Share on other sites

Hi Ben,

My cooler is from a power boat, it was lying arround in my workshop from a race engine I built for a race boat,

It is made of copper instead of ally but for all intensive perposes is exactly the same as a Laminova.

Would you like some pics.

Lara.

Link to comment
Share on other sites

Hi Ben,

My cooler is from a power boat, it was lying arround in my workshop from a race engine I built for a race boat,

It is made of copper instead of ally but for all intensive perposes is exactly the same as a Laminova.

Would you like some pics.

Lara.

Yes please. Are they cheaper than Laminova's?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy