<style> <!-- /* Font Definitions */ @font-face {font-family:Cambria; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Cambria; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style>We have a 1988 F-250 7.3l Diesel with automatic transmission. We bought this car some months ago with the intention to also buy a trailer to pull some small equipment. The car is set up with trailer hitch and a break system from former owners. The car was used in rather flat terrain before, but we live uphill on 2100 feet elevation over a 17 miles drive from the ocean side, whereas the last two miles a quiet steep.
A friend told me that we would burn out the tranny if we start pulling a trailer with maybe 3-4000 lbs. uphill. The tranny has a cooler which I belief was installed afterwards, not original.
The question is if we are at high risk to kill the tranny by use of a trailer? Especially as the car is quiet old now.

 

Ok maybe you have the e40d trans. First and simplest check is to draw the trans dipstick and see if there is a dirty or burnt look or smell with the oil. ATV usually has a colour from dye as an aid to differentiate it from hydraulic oils. I have never seen new oil with a dark color, usually red or blue. If it is dirty or burnt there are previous issues. Can you find a service history from po or shop?
Ask around your area for a good tranny shop, an expert can give you a good indication from a test drive often, at very little or no cost too.
What final drive ratio are you running? For laden purposes on hills a ratio 4,10 or bigger will be preferable I'm sure. Other guys in your area or familiar with these engines at altitudes may comment on ip settings to help.

 

old school c6 in '88.first year for e40d was '89.
you'll know if you can tow up steep hills by installing a trans temp gauge.if you can keep the pan temp 220F or lower,towing your max gross in July/August then your golden.if you can't then you'll need a larger aux cooler.

 

^^^Yep, keep it cool and it should be fine. These trucks were made to work, they're not afraid to.

 

Thanks southern-old-bold. The oil looks and smells ok. Unfortunately we don't have a history record of the car but we plan to go to a shop with it and have somebody look at it. The ratio on the tranny is 3.55

 

I see, the main thing is to keep the temp low. I also found this older discussion https://www.ford-trucks.com/forums/1...test-port.html on this forum. I didn't read everything yet. My question is if the temp gauge has to be installed to the pan or if it should be in the supply line to the trans cooler or if it doesn't matter?

 

i had a sensor in the cooling line,out from trans before cooling and it was too busy,nerve wracking and distracting.go with the pan.keep her between the ditches of 150-220F there and run 'er.

 

I finally made it to install a temp. gauge. I replaced the pan with a larger one and installed the sensor in the pan. First test drive: Shifting actually was smoother than before, I guess because of the fresh oil. But the gauge went up to 240º F and that's without pulling a trailer, no load in the back; just driving back home uphill. Is this normal? I thought I should keep my temp below 220º and specially having no load or trailer should keep it significantly lower? Any advice?
Thanks.
Pat

 

Did you flush the cooler when you changed the fluid? Maybe its blocked up some?
Also, the stock cooler should be part of the radiator, is it still part of the picture or was it bypassed and only the aftermarket is being used? Generally aftermarket coolers are added to help the stock unit out, not replace the completely.

Hopefully those auto tranny guys will be back, I'm a manual tranny guy.... But your answers should help point those guys in the right direction to help you out.

 

3-4000 pounds shouldn't be a problem with this truck.

No, it's a C6. This is a 1988 and 1989 was the first year for the E4OD.

No, that is the ratio of the axle, not the tranny.

It matters big time. The best place, in my opinion, is in a test port. I've heard that many C6s did not have a test port. I can't say if that's true or not, I never worked on a C6. If it doesn't have a port, the pan is the next best place. The hot line to the cooler is just going to scare you. Seeing 300F there is not unusual. The important temperature is what the trans is at, and the pan is a much better indicator of that then the cooler line.

Even for a C6 that's pretty hot. Are you sure the gauge is accurate? Do you have access to an infrared gun to get a second reading on the pan temperature?

 

No I didn't flush the cooler, didn't think about it. I might still do that to see if it is blocked.
I am not sure the car has a stock cooler for the trannny, I will check but maybe somebody knows beforehand?

 

I checked before to see if there is a test port and could not find one. So that's when I decided to install it in the pan.
I installed a new gauge, but who knows, even a new gauge can be faulty; so I will test with a infrared gun and see where it is at.
Do you know tf this truck has a stock cooler for the tranny? If the tranny really is running so hot, would it be advisable to get a bigger cooler in place?

 

I used to drive a 21 ft. Toyota Dolphin mini motor home, frequently up long mountain grades and small climbs like you are talking about in nearly 100 deg. F temps- 4 cyl 22R with a 4 speed. Of course it would overheat! So, I got an electric fan from a junked car and mounted it in front of my radiator controlled with a nice toggle switch on the instrument panel. Whenever I had to pull a long grade in warm weather I would flip that switch, the fan came on at high speed and that did the job! It gave me the extra cooling I needed to get over the passes or to my mountain hideout with no heating problems.

Oh yeah, hopefully your radiator is not too cruddy on the inside allowing heat transfer from the hot line coming out of the transmission through the heat ex-changer into the radiator coolant.

That's all I can think of.

 

OH NO! I wrote a long detailed post about things to check- clutch fan, how the auxiliary cooler is mounted, and other things but I LOST IT ALL!


That's why my last post didn't seem to fit in, it was assuming that my previous post had been posted.

Now I don't have the time to re-write that


Maybe I can later!

 

Yeah, if you find some time, would appreciate it, thanks.