Ok I have a question about a tuner. 99 F350 lb srw cc stock lift, 33x12.5's,

I have a Hypertech Max energy tuner for the pickup it Has two tunes for the trucks ( also programs Mustangs) the two tunes are based on gas octane 89 or 91 octane. Also, you have the couple of options on tranny shifting the first one is shifting points +/- by 100 rpms , and if you dont have a shift kit, the second option is to increase shift firmness.
Ok, I use my truck for everything, running around town/s, desert roaming, and towing my CampTrailor. Load weight I have know Idea the info tag has faded. its a 26 ft' with 12' slideout. I know its heavy because it squats the pickup pretty low. (too low for a 1 ton if you ask me).
Anyways Any suggestions on the setting for the programmer especially on the tranny part? I do have to tow 12 miles uphill at a 6-7% grade to get to the lakes. Also, what is the correct or best fluid to run in the my tranny. I flushed mine with Dextron/mercon 5.
Thankx for the help

 

Has the transmission (4R100) been rebuilt? How many miles on it?

 

Looks like you have '99 with V10?

IMHO, your very urgent first step for towing heavy is better trans cooling. The '99 came with a very large fluid to air cooler for the trans, but did not have a cooling circuit in the radiator. This may have been adequate for most, but it is not robust by any means.
The simple solution is to install a new radiator from a 2000+ model with trans cooling circuit in it. Actually, most replacements for the '99 would come with them as well as most radiator suppliers only make the one model. You have to add some fittings and hose to plumb it in (easy), or use lines from later model.
Now you have a very robust cooling system.

After that, add a trans temp gauge. I start watching closely at 220, and back off at 250. My stock trans is at 175K and has not been opened yet.

Then you can think about modifying the shift program and putting more power into it.

 

It has approx 188k miles and I bought as the second owner and I donot know if it was ever rebuilt, but I highly doubt it. After I had the tranny fluid spewing outt after a trip to the lakes. I flushed the tranny my self then and did not change the filter (as recomended) there was a little bit of junk around the magnet in the pan but it been totally ceaned and refilled with 22 quarts merco/dextron 5 + 1 Quart Lucas tranny lube.

I cannot afford to have it rebuilt. I am disabled and can't do the stuff anymore. formerer Automotive machinist and Chrysler Mech. Napa auto Manager.

 

Not trying to call you out or anything but wouldn't an additional cooling circuit in a radiator actually add to the heat in the fluid? The heat in the coolant from the engine would be warm causing trans fluid to warm faster. I would think an fluid-air cooler that trnasfers heat from hot fluid to cold air would work just fine in any circumstance.

 

The coolant in the radiator will reach a max 220 degrees on a VERY hot day and with a VERY heavy load unless your engine is freshly rebuilt or about to explode. Depending on the thermostat, which should be a 195 degree stat. Oh, it could get hot also if the water pump craps out out the thermostat freezes up. Which is what they are saying is the max temp for the Tranny! Even though hot, the coolant will cool.... My coolant runs on average 180. (stat is to low, especially in the winter!!!!)

 

Mercon is what you should use for fluid. I wouldn't adjust any settings on your tuner as it relates to the transmission. It always seems that whether gas or diesel, when tuners are added, the transmissions degrade quickly.

 

Any of the off the shelf tuners like you have with canned tunes are far from optimal performance wise. If you want to run 87 fuel I would just firm up the shifts a little (shift slip) around medium firmness. I wouldn't go crazy with the firmness on a older trans. Just a nice quick crisp shift. IMO you could benefit quite a bit by selling the Hypertech tuner and getting something more custom, especially a tow tune. 5 star tuning has a tow tune that works extremely well. Another thing that is important that adjusting the firmness will not address is the torque converter lockup. The custom tunes address that.

If you only have the factory trans temp gauge I would pick up a Scangauge II to monitor the trans temps more accuratley. If temps get too high a larger cooler would be a good idea.

Are you running a weight distributing hitch with your trailer? If not a WD setup would help you with your rear end sagging issue and help the rig handle better when towing.

Thats usually because A) The tune is garbage B) The tune adds a lot more power (diesels) When done properly tuning will not "degrade" your transmission.

 

No offense taken, a good question.

Unless you have serious problems, the coolant in the radiator will be WAY cooler than the engine. The temperature you see on gauges is almost always the block temperature. The thermostat restricts flow to keep engine at this temperature. It precisely meters how much colder coolant comes in from radiator to keep the coolant in the engine hot.

Even on the hottest days, the cold side of radiator should never get anywhere near 200.

Grab one of those little pocket IR thermometers and take some readings of the radiator yourself. You'll find it is usually well under 150.

And if the fluid to air cooler was big enough and got enough air, it would be quite adequate. But it would have to be big. Really big. Liquid to liquid intercoolers are far more efficient. Just a 12" copper pipe through the cool side of radiator can be as effective as a pretty big fluid to air intercooler. And since the radiators on these things are so immense, they can usually (and easily) keep up with cooling the engine and the oil and the transmission (well, if properly maintained!).

 

I agree. It does not directly degrade the transmission, but it is because of a tune that the trannys have problems.

 

I appreciate all the Ideas. I do have another few questions that have arised since the first question and answers, I looked at some tranny coolers today, I was thinking that a cooler rated for a class A motorhome and a dedicated fan. Very easy to install, and not too expensive.
Also, I have seen a lot of mention of '5 Star' tunning. How do I contact them and how do the custom tunning work? When I got the hypertech, I had no Idea of the tranny issues. It has made a HUGH impact in power and gasmilage. It had added 24 horse without any tranny adjusting and I get between 14 to 16 mph compared to 9 when I bought it. But I am interested in That 5 Star and also seen mention of 'SCT' 1 and the same? Also I am wanting to change my tranny fluid to synthetic. Help or hinder? Thanx for the help. Also going to change my ring and pinions to 3.73 from 3.55.

 

Contact

Like all the others, I am delighted with what Mike did for my truck. I strongly suggest calling and talking to him in person. Tell him your desires and concerns, and he will listen. One of those rare folks that still REALLY care about customer service!
You may have to leave him a message, but do so. He will call back and make it worth your while.

 

You won't notice much of a difference. As long as you use a high quality Mercon V fluid, using something like Amsoil is just a waste of money.