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OEM Trans Cooler

I vote for aftermarket. Your tranny lives and dies by the fluid temp. Better safe than sorry.
 
Get a trans temp gauge, Autometer makes the best gauges, then you'll know for sure. If the temps spikes, slow down or take a break, later add an aftermarket cooler.

I put one on my Chrysler Mini-Van with the Notorous rep for failing early A-604 transmission. Noticed several conditions where the tranny temp soars, found that all I had to do was take the trans out of OVERDRIVE and into 3rd to keep it cool. I suspect if I had not installed the Trans Temp Gauge, I would have cooked the trans several times by now, and would be replacing my A-604 like a lot of Mini-Van owners.

Cost about a $60-$75 to do the job, but its difficult enough to be more than a beginner could do on their own, most good shade tree mechanics could handle it easily. No more difficult than adding an aftermarket trans cooler, it differs in that you have to run some wires thru the firewall and mount the gauge somewhere in the interior.
 
x2 what Dirt & Rick said.
A gauge and cooler can be had for less than $100 (quite a bit less depending where you look & what brands you go with).
The way I look at it, it is cheaper than the tow to the shop to get it checked out if it does overheat.

Heres a link for a cooler & gauge install
http://www.naxja.org/forum/showthread.php?t=81124

HTH
 
I would not worry about the size of the cooler, if you have one you are good as long as you don't tow more than the vehicle is rated for in the owner's manual. The cooler has to be sized correctly or else Chrysler would be paying big in a class action case. Also designing a cooler is a black art, even it you make it larger you may get no more heat out of the fluid. AT BEST if the outside temp is 100F then the coolant will cool to 100F but no colder. Like the others said a temp sensor install would be good, more information is always better - full gauges vs idiot lights. I have considered a gauge but not found the need to install one yet, not sure where i'd mount the gauge.

I think a better question is to ask when the last time you changed your transmission fluid? I hope you are changing it at the severe duty schedule, if you do that you will be just fine. On my 88 XJ the transmission fluid change interval is 15,000 miles when you tow. If you are unsure of the mileage on your fluid then have it changed before you tow. The manual also says drive is 3rd when towing in hilly areas, and in 1-2 for more severe grades.

I never understand why people buy a vehicle and never think you have to change transmission fluid. I had a coworker tell me on my 86 Mustang 5.0 to just save the money I spent on 30K miles and use that money for a transmsision rebuild. I don't understand that thinking of avoiding preventive maintenance and figure on a hard failure.

If i may ask how old is your radiator? It may be partially plugged and towing at 100F will bring out the weakness if it exists. Also make sure the electric fan works, my XJ was running hot and I finally checked and I forgot to plug back in the electric fan, plugged it in and the problem was fixed.

Just make sure you have all you fluids topped off before the trip, carry extra coolant. It is good to practice the Boy Scout Moto "be prepared" but we are Jeep owners, goes with the breed.
 
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martin said:
I never understand why people buy a vehicle and never think you have to change transmission fluid.
I think it came from the 60's & 70's when people only kept vehicles for 75k miles at most, the vehicles were lower geared (greater torque multiplication = less heat) and the trans were stronger (but less efficient because the rotational mass was greater to get that strength and ruggitness).

No one changed trans fluid THEN, and often got away with it. Most of the manufacturers recommended NOT to change the fluid, it would last the life of the car, unless you were towing.

That false conventional wisdom gets passed down. I've had several friends ask me if their father was right and did they get ripped off by their mechanic, for things like;

"My dad said he never heard of a rear wheel alignment, you can't align the rear wheels and the mechanic ripped me off" Ummm, NO, your car has Rear Independent Suspension, it needs to be aligned, this isn't the 60's where every car was RWD with rear live axles.

"My dad says you don't need to change transmission fluid, its lasts the life of the car" Ummm, open your drivers manual and read it!

"My dad said that I don't need to change the timing chain on my car, they don't wear out" Ummm, you have an OHC engine with a timing belt that needs to be changed every 60k miles or it can break and destroy the engine.

"My dad says he never rotated tires and the front tires never wore out faster then the rear tires, he says I must have a bad alignment." Ummm, your car is FWD, the front tire will wear out much faster than the rear, you have to rotate the tires to keep them wearing evenly. You dad must not have ever owned a FWD car.
 
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Rick Anderson said:
I think it came from the 60's & 70's when people only kept vehicles for 75k miles at most, the vehicles were lower geared (greater torque multiplication = less heat) and the trans were stronger (but less efficient because the rotational mass was greater to get that strength and ruggitness).

No one changed trans fluid THEN, and often got away with it. Most of the manufacturers recommended NOT to change the fluid, it would last the life of the car, unless you were towing.

That false conventional wisdom gets passed down. I've had several friends ask me if their father was right and did they get ripped off by their mechanic, for things like;

"My dad said he never heard of a rear wheel alignment, you can't align the rear wheels and the mechanic ripped me off" Ummm, NO, your car has Rear Independent Suspension, it needs to be aligned, this isn't the 60's where every car was RWD with rear live axles.

"My dad says you don't need to change transmission fluid, its lasts the life of the car" Ummm, open your drivers manual and read it!

"My dad said that I don't need to change the timing chain on my car, they don't wear out" Ummm, you have an OHC engine with a timing belt that needs to be changed every 60k miles or it can break and destroy the engine.

"My dad says he never rotated tires and the front tires never wore out faster then the rear tires, he says I must have a bad alignment." Ummm, your car is FWD, the front tire will wear out much faster than the rear, you have to rotate the tires to keep them wearing evenly. You dad must not have ever owned a FWD car.

good stuff
 
Rick,

I agree with you the "I never changed it and never had a problem" seems to be common when it comes to automatic transmissions. I learned to drive in 1969 Camero and the owner's manual said to change transmission fluid at 25,000 miles. At 100K I talked my Dad into doing the first transmission oil change, my parents purchased the car new.

The same guy who told me at work not to change trans fluid in my mustang had a driveability problem. He finally asked me how to get a personal account for alldatadiy.com, got a subscription for his 95 crown victoria, read the TSBs. The 2 or 3 TSBs recommended the first course of action to change trans fluid. He read that and said "no, that can not be it". About 2 weeks later he changed the fluid and the problem was solved. You know I rubbed it in at every chance about his philosophy. Now he is like the apostile Paul after being struck blind. He is trans fluid change evangelist.

My Buick mechanic was telling me one day that I could have my transmission serviced on my Le Sabre but on some Pontiacs had transmsisions without pans, so factory fill for life. For some reason GM decided to used the sealed transmission on the Pontiacs. The only way to know if fluid is good or not is to take a sample and have a lab test it. That works just find for aircraft but for us mere mortals driving vehicles with 4 wheels it is less expensive to just change the oil than to pay for the lab test.

I wish I had a copy of the owner's manual, it also said to change shocks at 25,000 miles. All the cars I have driven since they make no comment about shock replacement interval.

Just remember some advice is timeless, other advice becomes out-dated by advances in technology. Just remember the car companies would not put maintenance internvals in the owner's manual if it was not required to keep the vehicle servicable through the warranty. They want you to come back because you find their brand reliable.
 
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