stupid trans temps

[digglesworth]

What acceptable? What's not? Mine levels off around 194-196 on the highway. But it'll get all the way up to 220ish in hilly terrain. I try to keep downshifting to a minimum and don't give 2 ****s about being in the right lane doing 50 up a steep hill. But I just made an extra stop to let it cool down from 220. I'm on my second external cooler and the fan runs continuously. Anyone wirh a stock setup monitor their temps?. I can't imagine the stock setup would yield any cooler temps since it's running right next to engine coolant. It's really starting to piss me off.

 

[06 H3]

I run under 200 but I'm properly geared. I have hit 230 with the trans cooler in the past. I'm running a 180 stat. Maybe you have lines hooked up wrong...what kind of cooler are u running? And size?

 

[adventr]

I'm still on stock trans cooler, but in this weather I run ~190. Have hit 200 sitting in stop and go traffic, but it cooled back down once moving.
I've got a big cooler with a fan that I need to install sometime.

Does your torque converter stay locked all the time running down the road? I'm pretty sure that's what keeps the temps down on mine. Converter stays locked so no slippage to create heat.

 

[amrg]

Are you on 35s? Im Running aftermarket wheels (34 pounds each to the stock 20s) on 35s, I usually do between 170 to 180 city driving (180 at 110* ambient). Did hit 190/195 but I was wheeling in extreme weather for an extended period of time ( 115* , 45 mins of hill climbs/drops with tires at 10 psi)
Alpha here with 4.10s (which sure doesnt help the trans temp wise)

In comparison, I was running 215* at 115* ambient while cruising at 65 mph before I decided to get a cooler.

 

[chaos254]

I have an external cooler(no fan) and highest Ive see on mine is 208. That is with 35s on really hilly roads. Normally I'm around 190

 

[digglesworth]

Yep. I'm on 35s. Wheeling this weekend with temps up around 90, I was sitting around 190 while running the trails in 4lo. I had one time that I was turning around in a creek bed so I had to do like a 36pt turn-about shifting back and forth from R to D (not rocking it). It hit 231 so I sat for a few minutes in N to cool it down. Whenever I was wheeling, the truck was in 2. I'm running a derale 12742. It's an 8-pass cooler with a 10" pusher fan. I never used to have issues until recently. If I'd have kept up with the flow of traffic today, I'm sure I would've hit 230+ easy... ImI'm not sure what's going on... It might be something crapped out in the thermal bypass valve affecting flow. I pulled the hoses off the valve on the cooler side when I swapped coolers and fluid poured out from the transmission through the bypass valve. It was cold so the bypass valve should've been closed and I shouldn't have dumped fluid from the trans side. I may try and replace that... But after that, I dunno. Transmission rebuild. I don't know anything about transmissions.

 

[jphh20]

I'm running 35s with a derale external cooler 13504 with a thermal bypass which opens at 179. In hot summer months I typically see temps in the 180-190 range with the highest spike at low 200s. Off-road I run in 4lo where possible to keep heat down which helps a ton. I'm not running a pusher fan and I am looking at this options for both radiator and the trans. I was also thinking of adding another cooler stacked because it seems on hot days it struggles to shed the beat on the highway on hilly terrains.

 

[06 H3]

I'm not convinced you need a rebuild I would for ****s and giggles pull the bypass valve and put a connector to connect the 2 lines back together and see how it runs.

I hit 230s with a trans cooler before. Before it I hit 256 once. That's cooking and people were surprised it had somehow lasted 140k miles and it was still perfectly fine but I did a rebuild when I pulled the 5 cyl and put in the v8

 

[amrg]

Maybe there is a constriction in your lines? That could force less oil to move and as a resupt ur trans builds up more heat? Check for hard bends

 

[CaseyS]

What is your engine coolant running? If your external cooler is working properly, the trans fluid should be cooler than the engine coolant. If the trans and engine temps are similar, the fluid is likely bypassing the external cooler.

 

[digglesworth]

Casey, I have a manual trans radiator w/ no internal cooler. I'm bypassing that setup completely and all cooling is done by the external cooler. My engine sits at 198 almost all the time. It can very a few degrees up or down but typically sits at 198.

Chris, I hit 251 a few weeks ago for a brief minute. I stopped the truck, opened the hood and let it run in N till it came back down. That is what caused me to try a different cooler with fan. I did a fluid change in case the fluid was scorched...

Amrg, I paid particular attention to the lines. The manual said avoid any radius' smaller than 5".

 

[06 H3]

Hmmm, that's weird. I would try bypassing the stat right now, it's to prevent overcooling but it's summer and seeing you can watch temps I would say try it and see the difference it makes it doesn't make and then track down what it can be.

 

[amrg]

Hmmm, that's weird. I would try bypassing the stat right now, it's to prevent overcooling but it's summer and seeing you can watch temps I would say try it and see the difference it makes it doesn't make and then track down what it can be.

Yeah bypass the stat. It could by itself be causing a restriction (and now with hotter weather you're noticing it). That would be a good way to start tracking the issue.
But when you say you run normally high 190s, leads me to believe the cooler isn't enough for what you need.

 

[digglesworth]

the new cooler has a higher gvw rating than the previous cooler i was running. it is a tube/fin design vs the old plate/fin. i dont think tube/fin is quite as efficient as the plate/fin. i do have another one of the new coolers that shipped later from another place. i was gonna return it but now im wondering if i shouldnt doube it up and run both of them in series...

 

[06 H3]

There are 3 types of coolers, the one I have is the most efficient, I took maxPFs advice. I will link it later when I'm home.

 

[digglesworth]

Thats what I had on there. I believe it's the 13503. I didn't see any plate/fin coolers with pusher fans. It'd have to be a custom setup to add a fan to one of those type of coolers.

 

[amrg]

Im running a 34K GVW cooler, trucool brand, and it is listed for applications that BYPASS oem radiators (apparently there are ones rated as the same GVW but are meant to run in series after the oem)

 

[digglesworth]

Do you have a part # for that one?

 

[amrg]

http://www.transmissioncoolers.us/category/trucool-MAX-cooler.html

Im running the 30K BTU one. I was worried that I would have fitment issues, but once I was at it I found that there is enough room for a 40K. (Planninh to swap the 30K to my I5 and put the 40K in my Alpha)

 

[SedonaBound]

Put a switch on that fan. Fans are counterproductive above 25-30 mph; especially pusher fans. On the trail at 5 MPH, its helping; when you get on the freeway, its just blocking air flow.

 

[digglesworth]

That's how I have it set up. It's not t-stat controlled.

 

[SedonaBound]

That's how I have it set up. It's not t-stat controlled.

Was it on or off when the trans temp got high?

 

[digglesworth]

Both. I'll try it again tonight with the fan off and see what happens.

 

[digglesworth]

Just took a little evening trip about 30mi away. Mostly highway. Hit 208 by the time I got where I was going. Went and ate dinner. Came out about an hour later and it was at 165. Drove home. Mostly highway again. Hit 210 by the time I got in the driveway. It's been sitting idling for 20 min with the fan on and it's dropped to 190. I didn't use the fan on the trip to see if that was blocking some fresh air coming in. I think the cooler isn't up to par. It's like the fluid is staying away from the trans for long enough to get cooled down. It's an 8 pass cooler. They make a 16 pass but it's too thick to fit between the condenser and Thorparts bumper. I don't know where to go from here... Double up this cooler, get the biggest plate/fin cooler I can fit in there and retrofit this pusher fan on that.... I dunno. Trial and error gets expensive... But so does a trans rebuild...

 

[CaseyS]

And I guess you are too far down the rabbit hole to go back to a series setup with the radiator cooler plus the external since you have changed your radiator.