'03 Discovery Auto Box problem.

Have read most of the threads, but can't seem to find assistance for my problem. Red temp warning light came on few times after long runs (85mph) and I decided to change oil and filter as precaution. Car was running perfectly, however, light still occasionally came on.

Just driven 1000 miles to Switzerland with long climb at the end and light stayed on throughout climb, despite stopping to let it cool twice. No smell of burning oil anywhere, however, there is oil smattered along off-side chassis rail, transfer case?(where rear prop and front prop meet) and bottom of torque converter. Obviously, I've just driven a long way and there is tell-tale mist on rear of car too.

Car is still driving fine, but there's obviously a problem worsened by the fact that the car was to be staying abroad. Only other sign of a problem was on climb a metallic noise/rattle could be heard when engine at circa 2500rpm Any advice would be much appreciated.

Chemics

The gear box has an oil cooler is it blocked with rubbish, are the oil pipe connections tight, is the fluid level still ok or is the temp switch faulty theres not much left that u can do yourself.

Regards

As I mentioned, am currently abroad and the car was to stay for a while. Where is the oil cooler located and is it possible to unblock or replace.

I've got tools and will have a go if accessible, thanks

Chemics said:

As I mentioned, am currently abroad and the car was to stay for a while. Where is the oil cooler located and is it possible to unblock or replace.

I've got tools and will have a go if accessible, thanks

Click to expand...

The engine oil cooler is integral with the radiator, the auto box fluid cooler is located there just in front and at the bottom. It is shown as a item in the parts book with brackets and nuts & bolts so must be a replaceable part also shown inline with the pipe work or as a pipe union entering the cooler is a "Switch transmission oil temperature".. LR speak for a thermostat i think. It has no electrical connections or none shown.. pt.no AMR4948 from vin MA081992.

Added to the above.. Just had a look at my car and the oil cooler can be seen behind the grill and in front of the rad it's round and has fins round it and pipes can be seen going 2 it..

Hope the above helps.
Regards

Thanks for the replies.

I think there's definitely a cooling problem and am confident the temp sender is working fine. Are there any aftermarket larger capacity oil coolers out there specifically for cars put under constant heavy load ie. Towing or in my case repeatedly climbing steep mountain roads?

Cheers

Chemics said:

Thanks for the replies.

I think there's definitely a cooling problem and am confident the temp sender is working fine. Are there any aftermarket larger capacity oil coolers out there specifically for cars put under constant heavy load ie. Towing or in my case repeatedly climbing steep mountain roads?

Cheers

Click to expand...

These are supposed to be good and not too expensive.

Take a look.

James

Hi I had the same problem when it was working hard (towing) it was the switch on the oil cooler radiator at the front. I fitted new one and that problem was fixed. You might need to enquire as to whether your car has a second switch on the transfure box mine didnot but looking at circuit diagram some do have and it puts on the same light so. Regards

Basically the problem is that you shouldn't tow anything heavier than a toy trailer with a DII auto. The box is basically not strong enough. I reckon very soon you will lose all drive. Have seen this too many times. One of the problems is (of course) the LR salesmen who will assure you that you could tow the Queen Mary if it were on wheels.

Feeling like a complete idiot here - I can't locate the oil cooler. I appears both pipes go into the front of two radiators, however, it doesn't appear to resemble an oil cooler. One of you guys suggested it may be integral, however, I'm not sure I follow.

It's looking like I should change this as first option and the go from there, especially as I can't get it back to the UK. Any other suggestions would be appreciated.

You may have an oil cooler IN the radiator! But probably it's a little long radiator under the main one.

Your one will try to cool the oil by wafting AIR over the cooler. This is pathetic, and makes not a blind bit of difference when you really need it if the oil gets hot.

The best oil coolers use WATER to cool the oil, by placing the cooler in the COLD end header tank of the radiator. This works! You will know you have this kind if there are two pipes taking gearbox oil into one end of the radiator.

I still go with the theory of replacing the thermo-switch(es) though. There should be one screwed into the bottom of the round right end of the cooler.

You may be able to cut down the amount the oil heats up by modifying your driving. The main source of heat-creation in an automatic gearbox is the TORQUE CONVERTER. If you are driving with engine revs too LOW, the torque converter will not STALL properly, and there will be a speed difference between the impeller and the turbine, and that creates a lot of heating in the oil. You would probably be better on hills to select a LOWER gear that lets you maintain 2,500 rpm AT LEAST thus cutting down converter slip to a minimum. You then drive as gently as you can but maintain 2,500+ rpm all the time till you are on the flat again.

Of course, best would be if you could choose to lock the converter clutch manually, so there was NO slip, but they don't think you are intelligent enough to be trusted to do that in your own car.

I bet there's a way this could be done .... a little switch somewhere .... that tips it to lock the converter clutch .... HHHmmmm.........


CharlesY