AutoTrans Idiot light

[nickg]

I have installed, egt and transmission gauges. The transmission temp. sender was installed on the hot side going to the radiator. The manuel states that when the transmission gets hot the light comes on in the dash.

The temperature that I've seen on my gauge running synthetic oil was aprox 280degrees. The light never came on. Does anyone know where the sending unit is located, and what is the temp for that unit to trigger it to light up in the dash?



2001 auto I just had T/C V/B DTT installed I will be testing this real soon be for going on an extended vacation. I would like to hear from you with some numbers so I could compare them with my rig. Nick

 

[pwr2tow]

Nick,

Welcome to the TDR, many people here able and willing to help with all kinds of problems.



I don't have any numbers but was curious, under what conditions are you seeing 280 degree temps and are the temps before the transmission upgrades or after the transmission upgrades or both. The more information we receive the easier it is to make a diagnoses. I'am sure someone will have the numbers you are seeking.



Ron

 

[DRR-24V]

280 Degrees !!!

If your trans temp is really 280 degrees, that is too hot. Something is wrong.

 

[cwsoules]

If I am not careful when backing my 5th wheel the transmission temp will rapidly rise. I've not gotten over 260 but I have pushed it.



It scares me and I'd love to find a way that will allow me to back up my 5th wheel without having to closely monitor transmission temperature.



I've also seen temperatures around 240 when towing in bumper to bumper traffic.

 

[nickg]

Auto TransIdiot Light

My first time pulling my 5th wheel 10,000lbs. going up a 6% grade 11 miles my temp. gauge read 195 degrees at 45mph.

I felt everything was great. The next year same grade except transmission/ egt gauges plus k/n filter were installed. EGT's read 1250degrees, transmission temp with synthetic oil was 280 degrees.

I pulled over 5 times to kool off. The sending unit for the transmission was in the line going to the radiator, pyro unit was pre/turbo.

Are these numbers normal and what did I do to my rig after the first trip?

Since then I have installed a dtt t/c v/b and I am about to make a trial run to see how everything handles. I also will try the (EDGE) pulse during my trial runs.

Does anyone know at what temp. does it take to light up the idiot light in the dash indicating the transmission is hot,and where is the sending unit located.

I feel like puting a sending unit in the deep mag pan with a toggle switch to monitor my temps. Maybe this will not be a concern anymore with these add on's... Nick

 

[stevek]

I was thinking the light came on at something ridiculous like 290-300* at which point the transmission would be toast...

 

[carson6]

300 degress

That's why it's called an idiot lite! By the time it turn's on ,you burnt it up !

 

[Evan A. Beck]

The light comes on at 270°F. Confirming you have just toasted your trans. *LOL*

 

[Chipstien]

Now that I think about it

I hit 280 with the factory trans and didn't get a idiot light either. Oh well, that is what the guage is for.

 

[nickg]

A/T Idiot light

E. Beck... ... with all the percautions taken stoping as soon as the temps. got to 250/280 I imediately pulled over to bring temps. back down. My transmission continued to perform just fine for months and thousands of miles later.

I wanted to insure the best performance possible while on a extended vacation. This is why I went with the upgrades that have been recomended here by other members.



Chipstien... ... . I was using a synthetic oil that would be able to with stand hotter than norm temps. approx 25/35 degrees with out creating damage to my transmission. When I purchased my deep transmission pan and differential pan this was recomended to me by

Mr. maghyteck himself. So I guess he was right, the transmission worked fine even after all the heat at short inervuls.



I was looking for the idiot light temp and location of the sending device to be able to monitor or hook it up to my transmission gauge.

 

[RustyJC]

Originally posted by cwsoules

It scares me and I'd love to find a way that will allow me to back up my 5th wheel without having to closely monitor transmission temperature.

Put an electric fan in front of the oil-to-air transmission cooler. If you don't want to use a thermoswitch, wire the fan into the back-up light circuit with a relay.



Rusty

 

[badams1]

Auto trans temts

I just had a BD T/C with trq lock and valve body installed and running ATF4 synthetic on my 2001 2500. They installed the temp sending unit on the T/C outlet line before the cooler up front. I was getting temps in the 280's F just setting in traffic without pulling anything. I called BD and they said the cooler knocks the temp down 100 F before the trans fluid returns. I put a heat sensor gun on the trans pan to check it out and got 170 F. I am installing the big Hytec pan w/ dual temp guage combo to monitor the difference. In the mail as we speak. The BD guys said that those temps are normal at T/C outlet. When im going down the hiway the temp drops to 170F at T/C outlet, I 'm locked up, makes sense. The T/C out let is the hottest temp location because of the T/C churning, and going from drive to nutrual lets it cool down. ATF 4 is good for much higher temps that others. I want to be able to control the max temp the fluid sees by using the netrual option. I also have the big Perma-Cool cooler w/ thermastat at 170F and fan to protect the transmission. Man this thing runs good now!

 

[DRR-24V]

Temps When Backing Up !!

Rusty and CWSoules:

I think if you install the Verhoef kit where you can use Low Range even on pavement you will see those temps drop drastically. No churning and slipping, just backing at almost an idle.

 

[RustyJC]

Re: Temps When Backing Up !!

Originally posted by DRR-24V

I think if you install the Verhoef kit where you can use Low Range even on pavement you will see those temps drop drastically. No churning and slipping, just backing at almost an idle.

Ummm... where do I bolt that Low Range kit thingie up on my 2WD 3500? Also, darned if I can find a transmission cooler on this 6-speed truck!



Seriously, adding the fan to the trans cooler is just something that worked very well with our 1996 V-10 automatic 3500. It worked even better after adding a supplemental B&M Supercooler to the factory towing package radiator tank cooler and oil-to-air cooler.



The root problem, of course, is lots of TC slippage (i. e. , heat) with no airflow over the cooler when backing a heavy 5ver. As you say, by increasing the mechanical advantage, the 2LOW kit reduces torque converter slippage.



Rusty

 

[DRR-24V]

OOH !!!

I can see where that might present a problem.

 

[RClark]

My 93 had a dual gage. transmission out(converter out) and pan. On a hill I could see 250-280 from the converter but the pan temp stayed under 180.

Going down hill with the Pacbrake on the converter out could reach 320 but the pan stayed at 145.

The pan temp is what is going into the transmission and it is the big worry.