External Transmission cooler? - Page 3

fmugur · #1 10-05-2012, 12:20 PM

I will stay with OEM just to avoid custom connections but I wonder why the heat exchanger does not do a good job anymore to keep the temperature to the coolant temperature.
I am thinking of taking it out and inspect it or buy a new one but the external cooler would do the cooling anyway.

fmugur · #2 10-07-2012, 10:05 PM

I installed mine as civdiv. The temperature is lower but I have to do some measurements to show the exact difference. It was a challenge to cut the return line and insert the new lines due the inner diameter differences.
An interesting thing when adding oil to the tranny was the temperature measured with IR vs. temperature from inpa. I got about 86 with the Infrared temperature reader and 102 with inpa. I know the temp sensor in the tranny is on the harness which is right at the fill plug lever. I expected the temp to be the same and I wonder why it wasn't. It could be inpa or the sensor in the harness or could be the oil vs. coolant or...
I tried to get the temp from gt1 but I couldn't find it easily. I will try again and compare the readings.

Anyway, so far I am happy with the 2-1 downshift that does not happen or at least it did not happen although I tried hard. Hopefully that was it.

civdiv99 · #3 10-07-2012, 11:39 PM

Sorry i haven't weighed in; i took a few weeks off and have been bouncing around CO & WY of late.

I used a coupla brass adapters to deal with the transition between the lines. Now, you DID buy transmission cooler hose, and did not use generic fluid or fuel line, correct?

Although you are way up there in metric-land, I assume the temps you indicate are F and not C.

Maybe clean that old radiator and get any gunk or debris outta the fins while yer in there, too.

fmugur · #4 10-08-2012, 12:34 AM

You scared me now. I used the hose that came in the kit which I thought it was for transmission.
Yes, the temperature was in F.

civdiv99 · #5 10-08-2012, 10:00 AM

That would have been an appropriate hose.

Quote:

Originally Posted by fmugur

You scared me now. I used the hose that came in the kit which I thought it was for transmission.
Yes, the temperature was in F.

fmugur · #6 10-09-2012, 01:57 PM

Thanks civdiv.
Here are the new values using the tranny cooler. The weather conditions were pretty much the same. 4C outside temperature.

The engine temperature shows 104C.
INPA engine temp 219F = 104C
INPA tranny temp: 203F = 95C
While cruising I got 189F = 87C

So the cooler works well but I still have a small harsh downshift 2-1.
Although I thought was related to the temp, most likely it's something else. It could be timing. It just happens at the same time the gearbox temperature reaches 200+F degrees.
I will keep an eye on it.

smiked1 · #7 04-03-2014, 04:46 PM

I know I'm digging up an old thread here, but I'm about to add a transmission cooler. What size are the factory hoses between the lines and the exchanger? I want to be sure I have the correct fittings on hand when I attempt to splice into these lines.

civdiv99 · #8 04-04-2014, 02:22 PM

Well, with caveat that the term "correct" is a reach in this situation, i think a 5/8 barb will work.

Just be sure you are comfy with this - you are going to cut both of the rubber lines about 10 inches or so before the factory cooler, splice in with a coupla adapters you preassy from the hardware store, use some higher end hose clamps, and add your aftermarket cooler of choice to the path. Pay attention to which hose is in, and which is out. Have the fluid go through the factory cooler, then your add on cooler.

Have clamping pliers handy to pinch off the factory hoses before you cut or you will be laying in a puddle with fluid dripping in your eye the whole time.

I personally don't find anything sacred in a 12 yr old car, but this kind of thing can make some folks a little concerned. Just so you know you are basically forging the path that seems right to you, under the car, with oil dripping in your eye. This isn't a well traveled road.

smiked1 · #9 04-05-2014, 04:09 PM

Excellent, thank you! I'm going to bypass the factory cooler completely. I'll have some 5/8" barb adapters, and some FI clamps ready when I chop those hoses.

V8 00USH · #10 08-18-2015, 05:54 AM

Sorry to bring this post back up again but I've got identical issues and I'm contemplating fitting an external transmission cooler. What I'm wondering though is has anyone changed the standard one before doing this?

My story goes like this...

I bought my X5 4.6is around 3 months ago on 99k. I got it back from picking it up and immediately clocked onto the harsh 2-1 downshift.

I scanned the gearbox for codes and it came up with the ‘too much slip’ code. Car went back under warranty to have the torque convertor replaced and the gearbox oil and filter changed.

I got it back but was still getting the harsh downshifts. I scanned it again but nothing came up.

I got under the car and had a look and could see the gearbox sump hadn’t been disturbed at all and so the filter hadn’t been changed. I took a sample of gearbox oil too and found that it was red and so they had used standard ATF fluid rather than the proper Mobile/Esso fluid. I complained and they agreed to take it back and do the filter and oil.

Unfortunately due to circumstances and time they didn’t get the car back for another couple of months or so and I’d done 3k in the car in the meantime.

I regularly tow with the X5 and the week before last I was towing a car trailor and the transmission got ‘stuck’ in 3th gear for around 10 miles. Nothing I did worked to try and get it to change – stopped the car, switched it off, holding it at certain revs, tried to go through the gears manually nothing worked. However after around 10miles it just changed into 4th then 5th by itself and then continued to work fine.

I scanned the gearbox again and got codes ‘3 Pressure Regulator EDS 3’ and ’34 Transmission Oil Temperature Sensor’. I hoped that the filter and oil change would rectify this the following week.

The car went back in to have the fluid changed for the proper spec and the filter got changed.

This weekend I towed again and again after around 2 hours of towing it again got stuck in gear – this time 4th gear only this time it continued until I got to my destination a further hour or so later.

After a bit of reading I found out about the transmission cooler thermostat. I got one ordered and fitted before I had to tow home again. Turned out it was the original one. I towed home and this time it was perfect with no hanging in gear although there is still a slight harshness with 2-1 gear after about 40mins normal driving. This to me still indicates a possible temperature issue especially as it’s perfect before this.

So I’m now contemplating replacing the standard cooler incase it’s slightly blocked and/or possibly adding an additional one too just to be safe especially considering the towing I do.

Any thoughts anyone?