Thread: P38 transmission cooler in a D1

Good timing - I've been having a bit of a look into this after JustinC recommended it in another thread.

There's a few places OS that you can buy them new online, but nowhere that I've found locally. I've been too scared to check the price of a genuine one.

Used one went recently on eBay for about $150

Steve

you got any links to those overseas ones?

fitting a bash plate wont affect the trans cooler unless you mounted the plate in front of the radiator
unless you are going into towing heavy stuff often its a waste of money and time.

cheers phil

Okay,

Yes, I have done the P38 transmission cooler on my 98 tdi D1 with aircon. Yes, it has been of benefit and was done in the efforts of trying to save my previous auto box from dieing (which unfortunately later it did anyway ).

I do a fair bit of sand driving and low range bush work and some heavy towing from time to time so a bigger cooler was highly recommended by local auto experts and AULRO experts (incl. JC). My old auto had overheated a couple of times so it was suggested that I get a bigger cooler on given the driving I do. About 8 mths later though the auto was slipping badly and changing gears all over the shop .

I will take some pics of the install, but essentially it fits in front of the aircon condensor, much the same way as my old 4 row cooler does, although the P38 cooler (12 rows) is slightly shorter in length (about 50mm), so some bracket fabrication work was required for one end.

I had new flexible cooler lines made up from the old swage fittings (at the end of the solid lines from the gearbox) to the new cooler by Pirtek as the old swage fittings had started to leak as well.

One other issue I found when installing the cooler is that being much taller than the old cooler and the position of it behind the grille meant that the bonnet safety catch (long hook bit) hit the top of the cooler, so I relocated the bonnet safety catch to work alongside the drivers side headlight.

Costs:

2nd hand P38 cooler: $250 (think I was taken on this one );
New high pressure flexible cooler lines from Pirtek: $160;
Bracket rejiggering: $0 (had lots of offcuts at home, made them to suit);
New oil for auto and to flush P38 cooler plus service kit: $160.

Sad news was after doing as much as I could.

Reco gearbox (after trying to prolong life of old one): $3500

Like I said, I will take lots of piccys, but I still have no idea about hosting them on this site , so I might have to send them to one of you by email.

My neighbour has just put one in his 97 diesel gas 300tdi . He tows a camper and also a horse float. Seems to look neat enough. He looks around on this site but doesn't post If no pics turn up I'll ask him to send one up.

Tony

I have one on mine, fits on top of the a/c cooler as described by goldey. I paid $60 2nd hand from a wrecker in Kelvin Grove, Rd Brisbane.
He had quite a few when I bought mine.

Originally Posted by dullbird

you got any links to those overseas ones?

I just found them searching through Google, but here's a couple:
Auto Gearbox Oil Cooler 2.5TD UBC100840 Island 4x4 - Specialists in Land Rover and Range Rover Parts and accessories for all models. UK and worldwide mail order.
Famous Four - New Parts for Range Rover P38A (Second Generation) 1995-2002 Models - Cooling & Heating

I think the way to go is getting a second hand one locally, but I was just a bit wary of whether they do have issues with leaking as they get older.
I'd like to know if they are something that never gives trouble, or if they get tired with age.

Steve

Over the years my 1996 Disco 300tdi has had a few overheated auto transmission warning light incidents, but only when towing caravans or fully loaded car-trailers up long and steep inclines (Mt Ousley, Kuranda, Lyall Hwy near Tarraleah, etc.)

The AMR4948 ATF sensor in the disco AFF cooler lines operates at 135 degrees C. ?€“ so when the warning light illuminates your ATF is already much to hot. In 2004 I installed a VDO temperature sensor in the auto transmission pan linked to an analogue gauge in the cabin. This has been invaluable in managing the ATF temperature when towing. I am comfortable running with ATF up to100, but I don?€™t like to run above 110 for any extended period or above 120 for other than a short time. By dropping down a gear, and by backing off and not pushing the car too hard, or even stopping for a cuppa and waiting for the transmission to cool down I have avoided cooking the ATF and an auto transmission rebuild. I have observed that, besides towing up steep hills, the gearbox oil gets very hot when towing into strong headwinds and stop/start towing in city traffic

For the last few years, 50% of my kilometres have been towing a caravan, so I decided to upgrade the transmission oil cooler. I obtained a few quotes, which varied between $550+ to $1000+ to install a second after-market cooler in series with the existing one. Besides the high cost, I was dissatisfied because of the vague responses given on of exactly how the job was proposed to be carried out.

After researching available oil coolers, and then reading a post by Goldy on the matter, I chose to replace the existing oil cooler with a P38 oil cooler which is 3 times larger.

I decided the tidiest and best long term trouble free set-up was to silver solder barbed ?€œLifesaver push-ons?€?, to the original steel pipe ATF lines (rather than run lots of hose), and while at it, permanently fix the well known problem of leaky swages on the flexible hoses section between the gearbox and the cooler (replacements cost circa $200)

How I did it -
1. Drain ATF from gearbox .
2. Remove the grill and the stone guard beneath the oil cooler.
3. Undo the oil pipes and remove the existing oil cooler & supporting brackets.
4. Make up brackets to support the P38 oil cooler and mount it using the same holes in the body. I used scrap 1.0 mm gal. steel plate. (See photo 1)



5. Remove the cooler pipes- undo the oil pipe support brackets, then -
(a) remove the lower gearbox oil pipe.
(b) removal of the upper gearbox pipe is more difficult because of the tight space. Remove the gear selector cable from the operating arm and its support bracket to improve access. I made up a long handled spanner by grinding an un-needed whitworth open-ender to size and fitting a pipe handle to reach the nut. (See photo 2)



Hang up lines to drain.
6. Using a hacksaw, cut the ends off the pipes at the oil cooler end. Save the pipe ends to make up screw-on/push-on fittings for the P38 oil cooler. (I used the old P38 pipes because they had more straight pipe before the bends).
7. Using a hacksaw, cut off the pipes at the back of the swaged fittings, except for the one with the oil temperature sensor ?€“ in this case cut the rubber hose off, then cut the swage off by sawing lengthways alongside the pipe. (I labelled all pipes to ensure no mix-ups when I put them back).
Also remove the ATF temperature sensor otherwise the thermistor may get cooked by the oxy during soldering.
9. Pre-order fittings and arrange a time with ENZED to do the job, then take pipes in to have 8 push-ons (part 39982-8-8) silver soldered on. These push-ons are nominally half inch sleeve but each sleeve needed to be machined by lathe to fit the half inch O.D. pipes, except the pipe from the oil temperature sensor fitting which was 13mm O.D.
I used ENZED at St.Peters; Graham was extremely helpful and they did a top quality job at a very reasonable price.
10. Temporarily fit the oil pipes back to the vehicle and measure the length of hose you need to cut to connect between each pair of push-ons. (See photo 3)

11. Remove oil pipes from the vehicle. Holding them in the vice, lubricate the barbs with ATF and push hoses fully on. (Note: once the hose is on, it will not come off, the only way to remove it is to slit it lengthways with a razor knife)
12. Refit the ATF temperature sensor. Make sure the face that the small copper washer seals against is good. Mine was not and it leaked under pressure when installed and I had remove it to file the face flat. Do not over-tighten the sensor or you may snap it off, like I did ?€“ they cost about $65 (but I did not bother because I use the sensor I installed in the pan).
13. Refit oil lines with new O rings to the vehicle and refill the gearbox with ATX. I chose to do a double (100KM apart) ATF change, upgrading to synthetic ATF with specs exceeding Dexron VI.

See photo 4 of oil cooler and photos 5a & b of swages eliminated.







Costs :
Used P38 Transmission Oil Cooler including cooler lines from ebay $87.00
Eight ENZED Lifesaver push-ons (part 39982-8-8) $80.00
Machine sleeves and silver solder 8 lifesaver push-ons to pipes $40.00
1.5 metre off-cut ENZED 300PSI Push-on hose (Part 611-8) $25.00
Four O Rings $00.80
TOTAL COST to solve 2 problems $233.00

Big thank you to Goldy for your post "P38 transmission cooler in a D1", also to p38arover for your post on "3.9 V8 engine oil cooler lines replacement" re solving the problem of leaky swaged hoses. Next time the swaged hoses of my engine oil cooler lines leak, lifesaver push-ons will be fitted to remedy this problem too.