1999 F350 Diesel Transmission overheats

[wrightracing.net]

Here is my problem, when ever the 4R100 transmission on my superduty F350 4X4 is under a load at slow speeds the trans heats up and will overheat if I do not watch it and pull over when it hits 200 on the autometer guage I have on the truck. It does not take much, I went up to Jamuel with a trailer with just quads on it and it started getting hot. If I am at 70mph no problem. Have any of you had this problem? I plan to put a B&M trams cooler in line it has a fan that comes on at 175, so I hope that will help?

What is your take on this problem, I know it is a problem with many F350 Diesels.:confused:

[Devin J]

Throw it away and put in an Allison transmission from a Navistar application. The tranny will outlast the engine.

[partybarge_pilot]

Depending on where your taking the temp from, 200 ain't that hot.

[wrightracing.net]

The sending unit is on the driver side of the transmission. When the temp gets to 210 the converter boils over. So it is that Bad. This is driving me nuts. It has been gone through by Ford twice in the last 3 years.

[partybarge_pilot]

Hmmm, sounds like not enough flow through the convetor or the convertors dead alowing the stall to be higher. It shouldn't be boiling at that low of a temp, 240 is more like it.

[FABRICATOR]

The gauge is probably in the sump so the numbers are late and low. But that's another story; it's still good for reference. I would check to see if the OEM cooler and lines are flowing well. Try blowing it backwards with shop air through a rag or sock and see if you catch anything. There could easily be crud in the OEM cooler from a previous failure. If there is, the new cooler will help but still won't solve the problem. An auxilliary cooler is always a good idea and you can try it with and without the original. They should end up working together, in series. Looks like a flow restriction somewhere.

[Moss2]

I am curious what happens when your "converter boils over". I have seen a trans at 325+ and dont think I saw this. New term for me. Have you dropped the pan lately?They have a fairly fine filter material maybe you arent getting enough through it if it is dirty. Most importantly is just do something soon I know you posted this same question a month or so ago. Hate to see trans #4 have to go in.

Ken

[johnnyweb]

something is wrong with either the cooler,lines, or converter. i have a 2000 and a 2003 with the same trans. my 2000 has 180k miles on stock trans and i tow 10k lbs all the time with it and have never had the trans over heat. my 2003 has 45k miles tow the same loads and the trans gauges does not even move on hills or not. there has to be some sort of blockage or something going on. if you have had the trans rebuilt or exchanged at a ford dealer they sould try to figure out the problem with you. also 200deg is not really that hot in my book if my race truck trans runs there im a happy guy. you could go with another cooler but i feel the stock cooler sould be fine for what you are towing. does the truck have some sort of ridiculous size tires on it with out a gear change?

[wrightracing.net]

I am going to put the trans on a flow meter in the morning to see if that is the issue. I am also going to put the B&M 500CFM fan tranny cooler on it with the thermo static switch to come on at 175. We will see. It only gets hot under a load at slow speeds so other than when I have the trailer on or 4X4 in deep sand at Pismo it is OK. I just got back from Pismo last week and the issue came up again so I need to deal with it.

Thanks all and see you at the 1000.

[wrightracing.net]

Hey all just an update, I put in that new B&M 500cfm tranny cooler. The thing is great. The temp never goes over 150deg around town even towing a 20ft trailer with a full size truck on it. We went out to Superstition and went through a long section of deep silt and never aired the tires down. The temp went just over 150deg about 160 but that was it. Great cooler. Here are some pictures of it with the bracket I made. I mounted it right behind the bumper air inlet to get the most air flow. I welded the mounting bolts to the outside of themount so the backside was flat and nothing would messup the AC cond.The mount is made of 2" X .120 flat stock and is a little over kill. I used a 1" hole saw and cut some holes in the bracket. I did try to use my dimple Die set on it but is started to bend the whole bracket. That is the first time I have tried to use my new dimple die's So .125 may be a bit much on a part only 2"wide with a 1" hole.

Thanks for all the feedback and Ken we might catch you at the 1000 look for 839 on a Gold F350 Chase truck. Have a safe Race.

http://www.wrightracing.net/wr/f350cooler1.jpg

http://www.wrightracing.net/wr/f350cooler2.jpg

http://www.wrightracing.net/wr/f350.jpg