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AW4 Operating Temp?

98 jeepjeep

NAXJA Forum User
Location
VA
I installed a temp guage on the Output line on the AW4 comming right out of the trans.
based on my reading it takes a while for the trans to warm up...so id say the radiator cooler myth is not true.

Anyway i let my girlfriend use my jeep to do a Paper route with ALOT of stop and go driving...She has used it for several weeks before but with no guage.
i asked her where it ran and she said 210 all night. So what is the normal Range? the aw4 should run at?

Also i have a BIG bar and fin cooler i will be installing today and bypassing the in radiator cooler.
 
the myth of the fluid needing to run through the radiator to heat it up.........From what im reading on mu guage my engine LONG comes to OPP temps before the trans even gets close to 150....and after a good bit of driving it settles around 170-180*
 
Your AW4 ran fine all these years without a temp gauge. Now that you have a gauge your are just worrying yourself.

My AW4 will hit 230 when on the output side when working hard.
I ran an external cooler for awhile without the radiator cooler. The temp would fluctuate a lot more and it did take longer to warm-up
 
Also remember, where the sending unit is placed will affect what temperature reading you get. With it placed on the output line of the trans, you will also be reading heat coming off the torque converter, which is outside your transmission. If your gauge is reading 170-180*, I'd bet your trans is a good 10* cooler than that. I'm in the process of placing a temp sending unit in the pan to read the fluid temp right before it enters the transmission. Ideally, I'd love to have one on input and output.
 
well i did get the big external cooler on today...but my lift kit also came in so i started taking the truck apart before i could get temp readings with the new cooler.
 
I have tranny temp gauges on 3 of the XJ's in the fleet and they all run at 170-180 on the return line even in extreme operating conditions (hazy, hot, humid, typical VA summer weather)

Wherebouts are you in the Commonwealth?
 
Your on the wrong side of the state! Too many people and not enough mountains. You need to come over our way and wheel with us.
 
Your AW4 ran fine all these years without a temp gauge. Now that you have a gauge your are just worrying yourself.
I only "pondered" my tranny temp until I put a gauge in. Now it's there for me to see. In the morning when it's cold (cold here is 30F) I hit the road and go down the hill. It takes 20 miles for the trans to get past 100F... I simply confirmed my thought that the trans would be hottter under load...duh! Towing up a grade, slow and go on a trail, traffic etc.

...so id say the radiator cooler myth is not true.

So, my take on the "myth" is that people think the radiator loop is a cooler. It's actually a heat exchanger with the sole purpose of heating the trans fluid to a decent operating temp. A 210F radiator could never cool the trans fluid to anything much cooler that 200F. My radiator loop is bypassed. Trans to cooler, back to trans. If I lived in Buffalo, I would keep the radiator loop plumbed.

Normal operating temperature for an auto trans is about 175 degrees.

Here is a general article on heat and auto trans fluid: http://autos.yahoo.com/maintain/repairqa/transmission/ques123_0.html

What "myth" are you speaking of?

Like I said about the myth...the only time my tranny gets over 180F is when I'm doing one of the things in red above. My gauge goes to 280F and I've pegged it out twice in 2 years. It just figures that if it's working harder it's running hotter. Cruising on a flat freeeway at 70 mph in 90F weather my trans never gets hotter than 150F.

TransLifeChartfromHECATInc.jpg


It also figures that you should check your fluid condition as well as the level regularly, especially if you run it hard. Don't run burnt fluid. DexIII or better, No ATF-4.
 
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