Tranny Temp Guage Readings

[CGLathrop]

Finally got the wife to give in and let me buy a tranny temp guage and cooler for my SVX. For the record its a 92 with 2nd tranny (that I know of) and about 120k miles. I dont have an auxillary tranny cooler installed (yet). I installed the temp sensor right before the exterior in-line tranny filter. This mornings temp was about 55 and driving about 75mph the tranny fluid got up to about 180. However, as soon as I stopped, the temp started to climb. The temp got up to 235 driving around base at about 35 mph, but not too many stops. Coming home I came through town. Temp was about 62 in town. Tranny went above 260 with all the stops. So, tomorrow I get the fluid flushed, and the cooler installed. Just thought I would let anyone know who might be interested in what the stock tranny temp is running at. And for a fairly cool day, I can imagine how bad it is when the temp outside is in the 90s.

Chris

[Vern!]

Usually my temps are between 130F (below which the overdrive does not want to work) and 195 (warm day after a hard run).

The highest I have ever seen it go is 218F, after a 25 mile drive up a 5000 foot mountain.

Daytime temps, with the AC on in traffic, are usually no more than 185F.
Nighttime temps, freeway speeds- no traffic are 140-160ish.

[1994SubaruSVX]

what kind of tranny cooler do you have installed? i just installed a b&m with 19000gvw's in front of the condenser and radiator.

[CGLathrop]

Its a tru-cool. Got it through JCWhitney (Stk No. 81UT0899X). Its also rated for 18,000 GVW. It measures 11" x 7 1/4" x 3/4". Its not the "tube and fin" but one with a mulitple path through honeycomb plates.. If that makes any sense. Installed it today. Highest my temp got up to now was 215. It was 70 degrees outside, and I turned onthe AC to make it go up that high. So your Tranny locks up at 130?? Mine wont do it until 160. I have read (somewhere on yahoo I think) that the TC is supposed to lock up at 50 or 60. Now im wondering (again) if there is something really wrong with my tranny. I thought 160 was kind of high for TC lock up. Guess I will plan a trip to spend some money at the dealer... :(

Hope this info helps anyone else out there who is considering adding a cooler.

Chris

[Vern!]

Mine is 11X10X0.75 inch stacked plate, between the condensor and radiator.

You say yours does not lock up till 160F, and you get a reading of 215F when driving in 70F weather

Mine shifts funny when colder than 130F, and in 70F weather I get temp readings of 180F tops in 70 degree weather (as in after a hard run)

I think the 30F difference can be attributed to you having your temp pickup before the cooler, and I have mine after the cooler.

Perhaps?

[CGLathrop]

The difference in temp is probably just as you said, having the sensor before / after the cooler. I have my cooler mounted in the front between the condensor and the radiator also. I wish I could lower the temp for TC lockup however. during the winter up here (when its -30) it will take my car about 30 minutes before it reaches TC lockup. And now with the additional cooler, I will have to come up with something to block the air from reaching it during the winter or I may never reach TC lock up. Did I ramble too much?

Chris

[svxistentialist]

Originally posted by CGLathrop
The difference in temp is probably just as you said, having the sensor before / after the cooler. I have my cooler mounted in the front between the condensor and the radiator also. I wish I could lower the temp for TC lockup however. during the winter up here (when its -30) it will take my car about 30 minutes before it reaches TC lockup. And now with the additional cooler, I will have to come up with something to block the air from reaching it during the winter or I may never reach TC lock up. Did I ramble too much?

Chris

Hi Chris
Rambling is good, rambling keeps you fit!:)

Thanks for the info on this. I am about to get my tranny fixed anytime soon, and I am going to fit a cooler also as part of the job. I had already decided on the Tru-cool, I have it listed on-line at Baker Precision Parts for $60, sized at 8" x 11". Is this the same as yours? I emailed them for a spec sheet, but they haven't bothered to reply.

For your low ambient temperature problem, you should strongly consider a thermostatic valve. You cut into the line going to your auxiliary cooler rad, and put in one of these. The valve will remain closed until the oil reaches a preset temperature. You should probably have this temp a bit higher than your lock-up level. Otherwise you will have "cycling" on lock-up as the cooler is kicking in and doing it's business. This may not prove to be harmful, but I suspect would be irritating.

Cheers

Joe:)

[CGLathrop]

Sorry it took so long for me to get back. Was in Cheyenne for the last 2 weeks and no confuser.. er.. computer (Lightning zapped the laptop!). Anyways...

My cooler is about 8x11... workes well on teh highway.. running around 80 - 85 mph the temp was around 220 (AC on). Shut off the AC and the temp would drop about 15 to 20 degrees. The temp outside was around 78.

<< For your low ambient temperature problem, you should strongly consider a thermostatic valve. >>

I like this Idea.. Not sure where to find one though.. Any ideas??

Chris

[svxistentialist]

Originally posted by CGLathrop
Sorry it took so long for me to get back. Was in Cheyenne for the last 2 weeks and no confuser.. er.. computer (Lightning zapped the laptop!). Anyways...

My cooler is about 8x11... workes well on teh highway.. running around 80 - 85 mph the temp was around 220 (AC on). Shut off the AC and the temp would drop about 15 to 20 degrees. The temp outside was around 78.

<< For your low ambient temperature problem, you should strongly consider a thermostatic valve. >>

I like this Idea.. Not sure where to find one though.. Any ideas??

Chris
Chris,

Jeggs have a lot of stuff on-line, I may buy my cooler from them. As they deal with racing gear, they probably have a thermostat valve available. Check this link:

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=27058&prmenbr=76&path=76%202443%202623

which would do the same thing, they are used for engine oil, but will work the same for ATF.

Joe

[htyei]

I never get above 160 after I installed my cooler(s)
I installed the gauge right before the atf inlet into the tranny, after all the coolers.

[svxistentialist]

Originally posted by CGLathrop
Sorry it took so long for me to get back. Was in Cheyenne for the last 2 weeks and no confuser.. er.. computer (Lightning zapped the laptop!). Anyways...

My cooler is about 8x11... workes well on teh highway.. running around 80 - 85 mph the temp was around 220 (AC on). Shut off the AC and the temp would drop about 15 to 20 degrees. The temp outside was around 78.

<< For your low ambient temperature problem, you should strongly consider a thermostatic valve. >>

I like this Idea.. Not sure where to find one though.. Any ideas??

Chris

Chris, further to this last one.

You might consider taking off your Tru-Cool and replacing with a B&M. I am going to put in a 19000 GVW like 1994SVX. The reason is, they have designed in a bypass setup into the fluid chambers. While the fluid is cold and viscous, most of it is passed back to the tranny for warming up. Once it warms, it gets the benefit of more cooler sections, so keeps the oil within a good operating range. Very clever of them, racing mentality I think. Might be a cheap route for you before winter sets in. You could always sell on the Tru-cool.

Joe

[svx_commuter]

The temperature out of my 92 is about 180F to 190F on the highway with 90 F ambient. I have a 16,000 LB tube and fin cooler in front of the condenser on the left side in series after the radiator and I reversed the flow through the radiator. This drives more heat to the thermostat and opens it sooner.

Runs cooler in stop and go with the a/c on and FANS running. About 190 with 90F air.

I installed a diverter valve to by pass the cooler in the cold weather. The honey comb set-up sounds like the way to go.

Going up hills will push the temperature up to the 120 range but it still drops the fluid temeprature down to about 180 when this happens. I haven't tried this in awhile but I know if I say on hills it will go over 230 F and keep climbing.

The t/c locks up around 140 to 150 F in the winter.

The thermometers are on the outside of the metal trans lines wrapped with insulation.

I want to know where to put the secret hole in that "tranny valve body" that is really a hydraulic control unit with many valves, pilot valves and solenoids!

[svx_commuter]

Originally posted by CGLathrop
I installed the temp sensor right before the exterior in-line tranny filter. Tranny went above 260 with all the stops. So, tomorrow I get the fluid flushed, and the cooler installed.
Chris

That seems very hot.:eek: I would like to know if the radiator has a lot of road dirt blocking the bottom section. I found this in mine.

[dromano]

Originally posted by svx_commuter


That seems very hot.:eek: I would like to know if the radiator has a lot of road dirt blocking the bottom section. I found this in mine. I found the same thing, I pulled out the bottom foam rubber, that's what was holding the crud at the bottom of the radiator. I wonder how much crap is in the condenser fins:confused: :confused:

[dromano]

Originally posted by CGLathrop
Finally got the wife to give in and let me buy a tranny temp guage and cooler for my SVX. For the record its a 92 with 2nd tranny (that I know of) and about 120k miles. I dont have an auxillary tranny cooler installed (yet). I installed the temp sensor right before the exterior in-line tranny filter. This mornings temp was about 55 and driving about 75mph the tranny fluid got up to about 180. However, as soon as I stopped, the temp started to climb. The temp got up to 235 driving around base at about 35 mph, but not too many stops. Coming home I came through town. Temp was about 62 in town. Tranny went above 260 with all the stops. So, tomorrow I get the fluid flushed, and the cooler installed. Just thought I would let anyone know who might be interested in what the stock tranny temp is running at. And for a fairly cool day, I can imagine how bad it is when the temp outside is in the 90s.

Chris Chris, where did you mount the gauge? Not too many spots.:)

[CGLathrop]

I pulled out the ash tray and put it in there.

[svx_commuter]

I think that the foam at the top and the bottom of the radiator is important. This prevents pulling of hot engine air back to the inlet of the radiator. This is more important in stop and go traffic when just the fans are running. I have used foam insulation to close off the paths around the radiator.

[svxistentialist]

Originally posted by svx_commuter
I think that the foam at the top and the bottom of the radiator is important. This prevents pulling of hot engine air back to the inlet of the radiator. This is more important in stop and go traffic when just the fans are running. I have used foam insulation to close off the paths around the radiator.

100% agreed commuter.

I think it is doubly important if you have an auxiliary cooler. The fans have to pull air through two matrices, need more suction, so big time you don't need pulling hot air from the engine bay above and below the radiator line. I would be on for replacing the foam with a rubber strip which would enforce all air coming through the front of the rads.

Any other ideas on this??

Joe

[dromano]

Originally posted by CGLathrop
I pulled out the ash tray and put it in there. :)Good spot. I put mine in there too. I used the ash tray light circuit to light the gauge. Havn't found a gauge power source tied to the ignition switch, gauge is on 24/7:eek: :eek: At least you know the fluid temp on demand. My first run today I got to 190, the sensor is in the auxillary filter. Next a fluid flush then fluid cooler install and synthetic fluid, my TC may never lock up again:eek: