Trans temp

[slapdappy]

basics:
"Fluid Temp VS. Transmission Life Expectancy
175°F = 100,000+ miles
190°F = 90,000 miles
210°F = 55,000 miles (Pressure Drops)
230°F = 25,000 miles (Valves Stick)
250°F = 17,000 miles (Varnish Forms)
270°F = 4000 miles (Seals & Clutches Burn)
300°F + = TRANSMISSION FAILURE"

"Those charts are somewhat misleading because they illustrate oil life at a constant temp.... BUT.... your actual trans temp is never constant. The basic rule is that it's time at temp that kills the oil, so based on temps alone, it's very difficult to plot in such a black and white fashion when the temps are constantly changing. The temp numbers change seasonally as well as by load, driving style, etc." fluid temp versus transmission life expectancy | ATF, Differential, Trans, Brakes, P/S | Bob Is The Oil Guy

 

[19963.4lsr5]

no.

My '99 (and subsequent year 3rd gens) sensor doesn't just trigger an idiot light at a preset temperature, it measures the actual temperature and sends this info to my scanguage. I believe it is located so that it measures the fluid at its highest temp.

I think the reason trans fluid temp is relevant is because it starts to break down at an increasing rate above a certain temp, which shortens its service life. So the temp after it is cooled and it enters the trans isn't relevant. The highest temp at any given time is what's relevant.

I'm just trying to nail down the wide differences in members oil temps. However I reedit my post.

On the jeep forums the AW4 oil pan fluid is suppose to be post cooler. aKA it comes out the trans after doing its work and then gets cooled and gets dumped into the pan.

I'm trying to find a hydraulic schematic it see it for myself. I have a AW4 manual but haven't looked through it yet.....

Also on the 96-98 trans I got to see if the temp sensor is 1 wire or three wire. The trans schematic I found for a 96-97 and 99 all show the same symbol for the trans temp. No switch symbol for the pre 99's

 

[slides]

I don't really care what the temp is when it comes back in. I just want to know the highest temp so the scangauge reads that since its from the pan correct?

Ever since I installed the cooler it reading higher temps in city/traffic driving up around 160-175 I think I need the satoshi grill mod for better air flow

 

[jgue467]

I don't really care what the temp is when it comes back in. I just want to know the highest temp so the scangauge reads that since its from the pan correct?

Ever since I installed the cooler it reading higher temps in city/traffic driving up around 160-175 I think I need the satoshi grill mod for better air flow

Right - highest temp matters most. I mean the incoming temp is interesting in that is s/b lower (so you know its working) but you're correct in really keeping an eye on the highest temp. I tend to agree with 19963. in that the sensor maybe right after the torque convertor cuz when my temps change (and it can be often) they change quickly either up or down pretty much in tune with the load (climbing, accelerating or the reverse).

I don't think 160-175 in moderate weather is to be unexpected though. Same here in texas right now...

 

[slides]

I am always amazed at how fast it changes temp once I left off the gas with in5 seconds it has climbed 10deg or higher

 

[slapdappy]

slides,
i suggest a larger cooler. when bypassing the radiator you lose the cooling capacity it provides. I installed the trucool 4544 with Low Pressure Drop design. BTU rating 20,000. The B/M 70268 is 13,000 BTU.

 

[nissanh]

I currently have radiator and an external cooler setup (not B&M) and it gives 132 F on a 90 F day.

How about the following transmission cooler? I found it in a Ford escape.
This fits well on the lower valence opening. Any suggestions? I am going to install this over this weekend.

Replace® FO4050101 - Ford Escape 2001-2004 Transmission Oil Cooler Assembly