I performed the test that measures trans fluid flow through radiator (per instructions provided by Mark K on a previous thread - Thanks Mark!).

Truck was recently driven about 20 miles. Trans temp was approx. 160 degrees when I removed rear trans line.

I placed rear trans line (hose attached to make it easier to point into bucket) in a bucket and started engine. Once flow was smooth (about 5 seconds), I moved hose over to a second bucket and let it flow into bucket for 15 seconds.

10oz is what was in second bucket after 15 seconds. What does this mean? I would venture to say....

1. Radiator may be causing partial blockage
2. If there is a trans fluid pump, it is not supplying the correct amount of pressure to move fluid through system
3. Some part in trans not allowing full flow of trans fluid when it exits and travels to radiator to be cooled
4. ????? Beyond my very novice abilities!

I hate to add a trans cooler without knowing if I have other problems that need to be addressed first.

Thanks

 

The next step is to rerun the test, except disconnect the line from the transmission to the radiator cooler. If the flow is still low here, then the transmission pump is probably worn out. If the flow is normal here, then the radiator cooler is plugged.

 

Second test performed. After 15 seconds, 1.6qts were pumped into second bucket. HUGE difference between test 1 and 2! I am pleased it is not the trans pump.

A couple of questions.

1. Is the 1.6qts at 15 seconds great, good, ok, or weak? (59K miles on truck)

2. Is there a way to clean the trans cooler portion of the radiator? If so, how?

3. If radiator can not be cleaned and radiator must be replaced, what type of radiator is the most preferred for high heat climates and towing up to 9000# (2 or 3 row, aluminum, plastic, combination of two, etc)?

Thanks

 

I do not believe that the cooler can be cleaned. Others may disagree with that. 1.6 quarts is very good.

 

Mark, what are your thoughts on by by-passing the OEM radiator trans cooler and adding this cooler. It is model 47391 (without thermal by pass). Are there any ill effects of doing this? Just trying to save on the cost of a new radiator, but don;t want to lose out on a positive benefit to the trans simply for the cost of a radiator.




transmissioncoolers.us: Tru-cool MAX coolers


I live in a warm climate area and will be towing to 9000# in warm areas (southwest).

Thanks

 

The radiator cooler is a VERY effective cooler. You will lose a lot of cooling if you bypass it. Where it really shines is low speed, especially backing. There is little to no airflow over the trans cooler when backing. Many '99 and '00 transmissions burned up backing up trailers when Ford deleted the radiator cooler. That's why the radiator cooler came back mid year 2000.

 

excellent, thanks Mark!

Is the E40D trans pump capable of pushing fluid effectively through the additional trans cooler if installed in line with OEM trans cooler?

 

Absolutely! Every Factory Towing package has an aux. cooler plumbed in series with the cooler in the radiator. Flow is through the aux cooler first, then through the in-radiator cooler.

Of course, all bets are off if you have a restricted or plugged cooler

I would not trust trying to "clean" a cooler. Even if the flow increased after running a solvent through it, what crud remains inside, to let go later, or plug up again later? It's not worth the risk of burning up a transmission.

 

[QUOTE=Torky2;14558788]Absolutely! Every Factory Towing package has an aux. cooler plumbed in series with the cooler in the radiator. Flow is through the aux cooler first, then through the in-radiator cooler.QUOTE]

I read that aux cooler is to run in-inline and AFTER the radiator cooler.

path of trans fluid:

Trans, to OEM radiator cooler, exits radiator cooler and flows to and through aux cooler, and then exits aux cooler and goes back to trans.

I believe the install would be as follows:

1. Remove lower lower trans line (return line) at radiator and attach aux cooler fitting to radiator (where you just removed the trans line).

2. Attach one end of aux cooler hose to this fitting and the other end back to trans return line that was removed from radiator.

Correct?

 

Wrong!

Correct.