Since I installed my gauges, I have learned how important they really are....

First off, my pyro is pre-turbo and my trans sender is in the hot line...

The truck has been working great and absolutely zero problems...I've been enjoying very acceptable temps, both empty and towing..EGT 1100 or less, trans temp usualy 180....I have found that nothing heats up a trans quicker than backing a trailer....A few times I've seen the trans hit around 220...

Yesterday I pulled my heaviest load so far on this truck and trailer...11000# of gravel...I grossed 23440#...(Dont tell weight watchers ) Pulling thru the hills near the quarry I flirted with 1150, and the trans never got over 180...When I got on flat roads, the trans dropped to 150 and egt's leveled off around 700....But when I arrived home and began backing the trailer into position, my trans heated up, and QUICKLY...200..Ok...220..OK...240-uh better watch it....260 I put it in neutral, kicked the high idle up, and let the fan pull some air through the cooler....It dropped back to 220 in about 10 minutes...Never got a warning light.

Obviously the overheating was due to the load and lack of airflow over the cooler...So I'm looking for added cooling on an as-needed basis....I'm guessing my solution will be an electric fan...I already have spare switches in place for power....Who has done this on their trucks? What are some other options?

 

When you are backing or positioning the trailer, the TC is constantly slipping, creating heat. The inability of the coolers to shed the heat is tied to 2 things:
1) The liquid to oil cooler does not have enough capacity to cool the fluid, vs. how much heat the tc is putting into the fluid.
2) The air to liquid cooler does not have enough capacity nor airflow to cool the oil vs. the heat the tc is putting into the fluid.

Keep in mind....trans fluid degrades as a function of temperature ond the amount of time at that temperature. The best thing you could have done is idle in neutral at a hi rpm; this pumps fluid without engaging the TC.

IF you really want to pursue this, i'd install 2 additional temp sensors: 1 in between the water to oil cooler and the air to oil cooler, and one after the air to oil cooler.

You need to understand how much temperature drop you are getting across each cooler and over MANY different situations. Obviously, the worst case scenario is when you are backing the trailer, but you need to understand all the situations you will put the trcuk into before attempting a solution.

It would appear that a larger water to oil cooler would help at low/no speed situations.

In a related situation, my brother called up last summer, after we put gauges in his dakota. He was concerned about the trans getting to 190-210 sitting in traffic. I told him to not worry about it, so long as he holds to changing the fluid at 30k intervals, as DC reccomends. The ATF+4 DC specs IS synthetic and will hold up to the heat MUCH better than dino fluids of the past.

In general, trans fluid is designed to last 100k miles at 170F. Avery 20F rise is a half life: 50K miles at 190F; 25K miles at 210F; 12.5k miles at 230F; 6k miles at 250F; 3k miles at 270F. As I mentioned above, this is a general rule of thumb, this ENTIRELY depends on how long the trans was operated at that temperature, and service intervals.

Keep an eye on the fluid color: if it starts deviating from the original red/pink color to dark blood red or into brown, get it changed ASAP! Also have the trans serviced (bands/filter) at the same time, by a reputable shop.

If you don't heat the trans to that temp too frequently, and hold to 30k changing intervals, you are probably Ok.

HTH

Tony

 

You might want to look into getting a Mag-hytec double deep tranny pan. They hold a lot more fluid and have a few cooling fins unlike the stock pan. This won't solve your problem but it will at least help. They cost around $250.

That amazes me it took 10 minutes to go from 260 to 220. Seems like a long time for such a short drop in temp. I don't have a tranny temp gauge yet so I have nothing to compare it to. Maybe try turning your A/C off before starting to back up since that is the first "radiator" in the airstream up front.

BTW how did you install the temp sender in the hot line? I want to install mine there also but haven't found a solution yet. Thanks.

 

has anyone noticed if the eng fan comes on as the trans temp comes up, as it dose with the ac, if not is there some way to turn it on.

 

Bd makes a auxiliary trans cooler that can operate from a Thermostat or on a switch click here I have one in my truck and I think it helps

 

The first thing to do is to use your four wheel drive and low range when backing your trailer if it's going to take some time and or you have adverse conditions. Your tranny will love you.

 

That is what I do also , put it down in 4 low and back up as long as you have 4x4 that is what I would suggest . A added plus is you can also do a better job backing .

 

You could try one of these, real nice looking setup with a lot of thought in the design, I've delt with them for some other items and was very pleased.


Super Cooler

Rick D

 

TonyB...Great post...I'll definitely be watching things until I find a solution I like....

handymantim...THIS is what I have installed on my tranny

DSjockey/RickD....That is along the lines of what I'm looking for...Thats an uwfully inexpensive investment compared to toasting my innards!


As far as using 4-low....I have used 4-hi a couple of times where I was backing the trailer up a grade into a driveway...I used 4-hi just enough to get it moved to more level ground...My concern is lock-to-lock steering when backing in 4wd, and breaking something in the front axle...


It seems that running a dump trailer just requires alot of backing....Just to get the trailer in a spot to be loaded, and then in a spot to be unloaded....BTW this trailer sure pours nice driveways with ease

 

It would be interesting to know how much difference the in line sender makes over having the sender in the tranny pan. I have the Mag-Mytek DD pan and the sender is currently mounted in the pan. Towed a 36 ft Tahoe Transport Toy Hauler today with temps in the mid 90's and the tranny temp never went over 180. Be nice to know how much difference there is though. Maybe I'll get that snazzy little line.
How much does that 5th wheel weigh anyway? I'm thinking 12K or so.

 

Howly cow your backing that kind of wieght in high range? ... Definately use 4lo and make everyones/things life alot easier... I really doubt you will ever do any damage to your trucks driveline, I have yet to hear anyone have any issues doing what your doing while using 4lo... Do the 4lo thing and check out your temps after that, I doubt you will have to spend any more money on anything.

 

Loaded like it was, I was about 16K....Trailer weighs in at 5000# empty....I crossed the scale loaded at 23440....so 23440 minus 10900# of rock=12540 truck and trailer...minus 5000 for trailer, so my tuck weighs in right at 7500#...Ill give 4-lo a try next time...

 

I don't think the weight has much to do with it all. I just backed my EMPTY 22' gooseneck into the driveway the other night. I have to jockey it back and forth a couple times to get it right where I want it. When I got done, I glaced at the tranny gauge and it was at 250° and climbing!!! I think reverse just generates a bunch of heat period.

 

Don't forget you need to be in neutral not park to circulate the trans fluid.

 

Not with mine....