Trans temp

FRD4LIFE · Jul 31, 2014

I am seeing high temps with my trans, 260 while towing and 200+ regular driving. It is a 00 F-350 with 6" lift and 37" tires. I had the trans rebuilt last year and just recently started towing a 28' trailer 6,500lbs dry. I put the 6.0 26-row cooler on and switched out my bypass valve but it is still showing 200+ with regular driving. My trans guy said my gauge is bad which is the only thing I could think too but the gauge isn't even a year old. It is the glowshift 3 in 1 gauge. What temp in the trans would flag a code and can I check the temp with a scanner to see if my gauge is really bad? Thanks in advance for your thoughts.

TARM · Jul 31, 2014

Glowshifts are about the lowest quality (popular branded) gauge set you can buy. I would definitely try another sensor and gauge. Make sure you change the sensor as well. Isspro or autometer would be my suggestion, in that order.

I am in no way a trans authority by any stretch with that understood I would hope you pulled over once you hit 250 and 255 for sure and let it idle till it cooled down. If you held 260 for any amount of time I would consider a fluid change. I forget what Marks exact numbers were but IIRC 250 for 25 max but he also said, again off memory after 30 mins of over 220 he would look for a place to pull over and let it cool down.

How did you plumb in the 6.0 cooler into the system or did your trans guy do it? Should be: trans>rad>6.0cooler>trans

Mark Kovalsky · Jul 31, 2014

Where do you have the sender for the gauge located?

260F is too hot if the sender is in the test port or the pan. If it is in the line to the cooler you're only warm, not hot.

Why would you think the gauge isn't bad just because it isn't even a year old? What does that have to do with anything?

lincolnlocker · Jul 31, 2014

what they said^^^ glowshifts are the bottom of the barrel but they are better then nothing. either try a new gauge like tarm suggested or hook the computer up to it and see what the factory sesnor is running at..

live life full throttle

Powerstroke Man 6.4 · Jul 31, 2014

Mark Kovalsky said:
Where do you have the sender for the gauge located?

260F is too hot if the sender is in the test port or the pan. If it is in the line to the cooler you're only warm, not hot.

Why would you think the gauge isn't bad just because it isn't even a year old? What does that have to do with anything?

WHS^^^

TARM said:
Glowshifts are about the lowest quality (popular branded) gauge set you can buy. I would definitely try another sensor and gauge. Make sure you change the sensor as well. Isspro or autometer would be my suggestion, in that order.

I am in no way a trans authority by any stretch with that understood I would hope you pulled over once you hit 250 and 255 for sure and let it idle till it cooled down. If you held 260 for any amount of time I would consider a fluid change. I forget what Marks exact numbers were but IIRC 250 for 25 max but he also said, again off memory after 30 mins of over 220 he would look for a place to pull over and let it cool down.

How did you plumb in the 6.0 cooler into the system or did your trans guy do it? Should be: trans>rad>6.0cooler>trans

WHS^^^

Sounds exactly how my old 7.3 was. 210-220 normal driving and 220-260 (Off of the factory sensor) towing (1 yr old Ford reman). Trans finally gave up put a new ford trans in (trans ran hot same temp) did a fluid flush bam no overheating Did you do a fluid flush when you swap out the cooler? My trans ran cooler when I flushed it. 180-190 ND 190-220 Towing. I had a little tin fin cooler though... didn't have enough time to the 6.oh cooler on before I sold it. 160/100's injectors and 35 inch tires stock height.

FRD4LIFE · Aug 1, 2014

The sensor is in the test port right above the pan. I guess I just thought the gauge wasn't bad because it has been consistant at those temps since I installed it. So it is probably bad from the start. Looking at the fluid it is still bright red doesn't look or smell burnt but I do not know much about transmissions.

Yes I did pull over at 260 to let it cool down. Wouldn't a temp of 260 throw a code or fluid start to vent out of the trans?

Powerstroke Man 6.4 · Aug 1, 2014

FRD4LIFE said:
The sensor is in the test port right above the pan. I guess I just thought the gauge wasn't bad because it has been consistant at those temps since I installed it. So it is probably bad from the start. Looking at the fluid it is still bright red doesn't look or smell burnt but I do not know much about transmissions.

Yes I did pull over at 260 to let it cool down. Wouldn't a temp of 260 throw a code or fluid start to vent out of the trans?

270 = limp mode and flashing O/D light

TARM · Aug 1, 2014

Mark Kovalsky said:
Where do you have the sender for the gauge located?

260F is too hot if the sender is in the test port or the pan. If it is in the line to the cooler you're only warm, not hot.

Why would you think the gauge isn't bad just because it isn't even a year old? What does that have to do with anything?

What is the ratio between pan/test port vs outlet to the cooler? How many degrees difference? i.e. 250 pan/test port vs ??outlet to cooler?

lincolnlocker · Aug 1, 2014

TARM said:
What is the ratio between pan/test port vs outlet to the cooler? How many degrees difference? i.e. 250 pan/test port vs ??outlet to cooler?

are you asking about the temp between trans to the cooler(pre cooler) or from cooler to the trans(post cooler)?

live life full throttle

Mark Kovalsky · Aug 1, 2014

FRD4LIFE said:
Wouldn't a temp of 260 throw a code or fluid start to vent out of the trans?

No, and no. A code is stored at 270F, and there is no temperature where a properly filled transmission will vent fluid. The only time a transmission will vent is if it is overfilled and overheated.

Mark Kovalsky · Aug 1, 2014

TARM said:
What is the ratio between pan/test port vs outlet to the cooler? How many degrees difference? i.e. 250 pan/test port vs ??outlet to cooler?

That depends on operating conditions. There is no ratio. Outlet to the cooler will be hotter. It might be 5 degrees, or it might be 150 degrees. It depends. There is no one answer.