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Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go hereXJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.
Well, a buddy of mine owns a tranny shop here in Prescott.
He used to live in Wisconsin. He's told me stories of over-cooling transmissions in extremely cold weather.
I know they say heat kills transmissions. Not ALL heat. Just too much heat.
So, our body temp is supposed to be 98.6*, right?
104* could kill ya.
So, should we shoot for a body temp or 60*?
No. We'd die............
Right-on. Outlaw Star recently described the scenario inside a AW4 that is not up to operating temperature. It's not good. I will have to find that post..
I have plans for next spring of mounting a B&W aux trans cooler, and I was planning to mount it before the fluid goes to the radiator. My thinking on this is that it will pre-cool the fluid during hot weather without allowing it to get too cold while driving on the highway in the winter like it might with the aux cooler after the radiator.
Judging from past few posts, it would appear that others are in agreement, though I wouldn't mind some additional thoughts. I live in DC but take the Jeep up to northern New Hampshire a bunch in the winter.
I cut the radiator out of the equation when installing my trans cooler. I have a thermal bypass valve to install to allow the trans fluid to heat up to temperature before flowing through the cooler. I need to get on that!
So before or after the original radiator-mounted cooler?
The instructions that come with the cooler say after, but from what I've seen on various auto forums (not just Jeep ones) it really doesn't matter and most people who tried both only see a few degrees difference between mounting before and after the factory cooler. Just like B&M says not to mount their coolers with the fittings pointing down, but some Ford trucks came with the same cooler from the factory (Dana makes B&M's coolers) with the fittings down, and several people on this forum and others have mounted B&M coolers with the fittings pointing down with no ill effects.
^ Tube type coolers can be mounted in any direction. But stacked plate coolers should not be installed pointing down. Air could be trapped in the top reducing its efficiency
The heat exchanger inside the radiator is to keep the transmission in it's optimum heat range........
How does it keep the tranny in it's optimum heat range? Does it maintain that heat range using a thermostat like the engine cooling system has? Any idea what numbers that optimum heat range would be?
Originally Posted by cruiser54
It's a trans heater also:
Any idea at what point/temp it would become a heater?.....and at what point/temp would it become a cooler?
Originally Posted by IJM
I have plans for next spring of mounting a B&W aux trans cooler, and I was planning to mount it before the fluid goes to the radiator. My thinking on this is that it will pre-cool the fluid during hot weather without allowing it to get too cold while driving on the highway in the winter like it might with the aux cooler after the radiator.
Judging from past few posts, it would appear that others are in agreement, though I wouldn't mind some additional thoughts. I live in DC but take the Jeep up to northern New Hampshire a bunch in the winter.
When u get your B&M auxiliary cooler, the B&M instructions will tell u to mount the auxiliary cooler in-line with and AFTER the Factory cooler........which is exactly the way the Factory mounts their optional auxiliary cooler.
Again, if u jack around with the OE Factory tranny fluid cooling set-up, u best have some way to monitor fluid temp just to be safe.