I checked today with a gun: with the gun I had 140º on the pan and my gauge inside was almost at 180º. So I think that gauge is bad. Will try to get it replaced under warranty or get my a different ond. Any recommendations?
Thanks
Pat

 

Can't re-write that post I lost until about 8 hrs from now but check your clutch fan- try to spin it my hand- it should have a lot of resistance and not spin at all when you try to spin it by hand- when engine is warmed up and you shut the engine off the fan should stop at the same time as the engine and not continue to spin at all.

I've read about everything on transmission temp gauges on this site and what they should read depending upon where they are placed is a bit confusing - Where exactly in this new bigger pan did you locate the temperature probe or sender?

That is a long grade you are climbing- I imagine a lot of switchbacks- what speed are you driving up it and what gears? Point being not a lot of airflow through the auxiliary cooler at low speeds and I don't think the converter locks up until 3rd gear at 35+ mph so the transmission will probably get warmer at lower speeds and stop and go driving - depends then upon the fan mostly.

Last thing which I'll get to later is the auxiliary cooler itself- and how it is hooked up.

Also, how far is the exhaust pipe from the location of the sender? I had a full size Cherokee- rugged mountain use carrying weight- the exhaust pipe from the manifold got bent and dented and it was very very close to the transmission and pan contributing to higher transmission temps. Just something to be aware of because that pipe gets very hot!

Sounds like you are just about ready to have a great tow vehicle for your trailer.

Good to see someone taking the care to do everything right on a truck that's 27 years old.

As per a previous discussion about converting it to a manual transmission, I would stay with the C6 if you can, for LOTS of reasons - really a tough transmission - your location and the type of driving you'll be doing in Hawaii, stop and go traffic - especially on steep hills- if you have to stop on a hill and someone pulls up 6 inches behind your trailer you won't have to slip the clutch to avoid rolling back into them when you start moving- just a lot easier to drive in so many circumstances than a manual and I don't imagine you'll be driving thousands of miles on flat highways like here on the mainland so the better fuel economy of the manual probably isn't that important.\

I have to run run out of town to pick up some parts for my truck and I'm running late.

BTW, mine is a 6.9L N/A. I saw a video of a guy with an older 6.9L than mine pulling 37,000 lbs combined weight with a gooseneck trailer and 34,340 lbs scale weight another time and he went up a long grade with that load. Slow going up the grade but Very Impressive! I knew then, I wouldn't have to worry about towing my little 4,000 lb trailer with another ton in the back of the truck over a few mountain ranges.

I don't know if you will benefit from an exhaust gas temperature (EGT) gauge with the size/weight trailer you are pulling and the distances you will be pulling. My truck has one but I need a new temp. probe.

 

I changed the fan clutch about 3/4 year ago - still ok.

usually 45-55mph in 3rd gear. There aren't to many stops, so it's a steady drive but like I said the last two miles are really steep.

I made some pics today:


The sender is in the upper back. I was careful not to have it to close to the exhaust, same is for the wire going to the gauge. I's still aiming to get me another gauge, don't trust this one.

I also looked at my cooler situation: There is a stock cooler and then the line goes to the auxiliary
cooler, which looks like this:


The picture is not so good, I hope you can see it; in my opinion the auxiliary cooler is quiet small. So this might add up to a hot tranny. I was thinking to swap it for something bigger. I have a cooler which was used for a AC in a tractor and is just sitting around; it's a lot bigger and sure would help.



Is that a good idea or better to get something different?
Thanks
Pat

 

That's the original auxiliary cooler that came with the truck from the Ford factory, at least on trucks with the 'Tow Package' (Trailer wiring harness- hitch).

It looks identical to the one I removed and replaced with a much better one. Mine was tube and fin, 4 inches high by 11-3/4 inches long. It had been leaking and the lines had been cut and plugged with bolts- the original lines routed back through the fittings on the radiator.

It had leaked fluid into the copper cooling fins of the radiator which then filled up solid with dirt and it looks like old dry grease and dirt packed into the fins. The copper fins are very old and very fragile on a 28 year old radiator - too fragile to try to pick the dried oil/dirt out without destroying the fins so I just left it. It's only an area of about 3 inches by 5 inches and that is a big and heavy radiator. The inside of the radiator is still very good (from what I can see) Regardless, a cooler leak or leak from the old hoses is something you want to avoid.

This cooler may have been fine and quite adequate when everything in the truck was new but I wouldn't expect it to be doing so well now after 27 years.
I should cut my old one apart this weekend and see what the inside of a 28 year old cooler looks like. If the tubes are not clean inside then they are not going to transfer heat very well - same with the condition of the heat ex-changer in the bottom tank of the radiator. I'd like to know what that looks like after 28 years too. Considering what the bottom of a pan and magnet look like at a transmission fluid change leads me to wonder! Had I thought of this at the time I would have probably flushed the heat ex-changer with a cleaner of some sort.

I DID install a MAGNEFINE filter in the return line to the transmission and I used Full Synthetic transmission fluid so those items should help some. BY THE WAY:, If I remember correctly the main reason for keeping the transmission fluid cool (within that operating temperature range) is because above certain temperatures the fluid begins to break down and does not provide adequate lubrication and other properties. Full Synthetic transmission fluid maintains it's properties at considerably higher temperatures. (Now ya tell me! huh!). I just read a lot before I make decisions and I have much more time to do that than most people. I used Dexron III/Mercon, I think it was Valvoline brand.

You've done such a fine job on everything else, pjcat, and spent considerable money and time to get your truck ready to tow. A new plate and fin style cooler is relatively inexpensive and easy to install - you just have to decide what size and how to mount it. (Take your time figuring out the best way to mount it. I think I paid about $35. plus $5.00 shipping for mine from Rock Auto Parts. It's 11-5/8 in. by 11 in. and rated for 18,000 lbs combined weight.

Here is the topic I started on that job with some photos plus contributions from others. That is the largest size I could install without extending it under the vertical bracket which would have required the cooler to be right next to the A/C condenser - I preferred the 3/4 inch air space between. One size smaller would have been more than adequate for my use.
https://www.ford-trucks.com/forums/1...er-cooler.html

ALSO, I did a google image search "install transmission oil cooler" or variations of such terms to find images of how other people have done it. I recommend that.

Personally, I would be hesitant to use the A/C condenser coil from the tractor, mainly because I don't know how much restriction it would have to the rate of flow from your C-6. The A/C system I think would be under considerably more pressure and less flow rate as from there it goes through an expansion valve.

I think you will be fine with the fluid you have now with a decent cooler.

Too tired to write any more now..

 

Thanks Fixnstuff for all the excursion.
My way to go for now is to get a good temp gauge, a new auxiliary cooler and a inline mag filter. I will do some research before buying a cooler about what size to get and check out the available room in the truck. I guess that's about the best I can do for now to improve the situation.