Here's the factory trans cooler vs the new one:
Getting mixed advice about trans temps
- Thread starter Cubey
- Start date
With the fan you can mount it just about anywhere. I have a flatbed truck with the cooler mounted behind the transmission, still gets natural airflow too.
You need one twice that size for that type of vehicle and a fan, you can front mount the fan. There are plenty of spots to mount it.
I recommend using the radiator mounted cooler in conjunction with the auxiliary cooler.
Converter outlet temps can get quite hot, I've seen 400°F in some extreme/high stall applications......But what's important is Sump Temperature. Until you get a temp probe in the pan, You're not seeing the whole picture.
Flushing trans cooler/s isn't usually a standalone service, It's part of the R&R of the transmission. Whether or not I'd do it heavily depends on my work load.
Converter outlet temps can get quite hot, I've seen 400°F in some extreme/high stall applications......But what's important is Sump Temperature. Until you get a temp probe in the pan, You're not seeing the whole picture.
Flushing trans cooler/s isn't usually a standalone service, It's part of the R&R of the transmission. Whether or not I'd do it heavily depends on my work load.
Twice the size of what? The old or new? The chassis is rated 11k. The new cooler is rated 29k and is about 3x as big as the factory cooler.
Again, there's no room for a fan. The "slim" fans are 2.5" thick. There isn't 2.5" between the cooler and the A/C condenser and there isn't 2.5" between the cooler and the grill.
Yeah. One way or another, it's gonna get flushed and tied in. If I have to do it myself, so be it. I'll filter the return line as best I can after flushing it.
The instantaneous ATF temp in the line out towards the cooler is simply considerably hotter than the bulk fluid temp, i.e. the sump. You need to meas sump temp to know just how hot your ATF is getting. Having in-radiator loop is important for wintertime as it heats the ATF. In cold weather the aerial ATF cooler (and no tank heater) can end up overheating the trans due to restricted flow...
It sounds like you've got a good plan. I would to the flush and route to the radiator, then the auxiliary cooler, with the inline filter on the return line.
You've put your temperature gauge sensor on the hottest part of the system, FYI. There is a pressure port on the drivers side above the shifter where you could tap in which will be closer to the pan temps, but the best place to have it is in the pan as has been said.
You've put your temperature gauge sensor on the hottest part of the system, FYI. There is a pressure port on the drivers side above the shifter where you could tap in which will be closer to the pan temps, but the best place to have it is in the pan as has been said.
Yeah. I was just worried that it might be harming the fluid. Valvoline doesn't list any temp specs for the non-Maxlife Dex/Merc, that I can find anyway, but assuming it's the same... Maxlife says it can stand up to 280*F for one hour.
I'm usually not in very cold climates but I do get what you're saying, if I ever found myself in one suddenly for whatever reason.
Yeah I expected it to be crazy hot. My comment above in this reply was my reasoning, wanting to see the absolute max temp the fluid was seeing, even if it's a small amount coming out of the trans and going to the cooler through a 5/16" steel line and rubber hoses. Yeah it's not enough data, which is why I'm sinking another $300 into a +2qts deep aluminum pan w/ a probe bung, plus a second trans gauge.
This thing is my home and my only highway capable vehicle, so I need it to not crap out on me every few years and cost $2500 to rebuild. I've owned it 3.5 years so far and I have no plans to get rid of it anytime soon, if ever. If it gets undrivable in a wreck and is beyond feasible repair, I'll be stripping off everything off of it that I can before it goes to the bone yard and save the parts for another C6 Ford/RV. In fact, I have an F250 with the same engine and trans sitting in a relative's back yard down south because I had it before and I can only drive one vehicle at a time, so they are storing it for me. It lacks turbo though and has a much higher mileage engine.
The steel cooler lines all got sprayed with brake cleaner then blown out with air before the new trans was installed, so those should be fine. The aux cooler is brand new, and it got all new hoses, so everything was new or cleaned/blown out before it was attached to the new trans. The only thing untouched (and isolated) is the rad trans cooler.
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You and other posters have already mentioned my suggestions--Flush it yourself with the Lubegard kit and plumb it back through the radiator with a Magnefine filter in the return line. Since you plan to change the pan, this is an application that I would refill with a synthetic that meets specs.
Are the lines really 5/16? I would guess at least 3/8 from my experience with lighter-duty vehicles. Magnefines come in 5/16, 3/8, or 1/2 inch sizes.
Are the lines really 5/16? I would guess at least 3/8 from my experience with lighter-duty vehicles. Magnefines come in 5/16, 3/8, or 1/2 inch sizes.
Dexron VI is bloody expensive ($30 per 1 gallon, or $22/gal for a 5 gallon bucket). Compared to about $17/gal for Valvoline Dex/Merc. Plus, most of the fluid is in the torque converter and that's annoying to drain.
A complete drain and fill takes about 4 gallons with the big cooler with the shallow 2WD pan. With deep, it's gonna be about 4.5 gallons.
Maybe after the break in period of 2500-3000 miles, I'll switch to Dexron VI since it claims to be compatible with Dexron III which in turn should be compatible with Dexron II, which is what the dipstick calls for. Even at higher temps, the existing Dex/Merc would probably hold up for that amount of time.
In about 200 miles, it's going to get the deep aluminum pan for better cooling, plus the rad cooler tied in, so odds are it'll be fine.
Yes, the lines are 5/16, or at least the output (hot) is. The B&M trans temp gauge kit came with 5/16 and 3/8 compression tees for the probe. 3/8 is too big, 5/16 is what fit. I ordered a 5/16 magnefine.
When I had my avalanche,I ran a tru-cool lpd cooler, it's much beefier and more btu drop than almost any other.
Tru-cool LPD 47391
40,000 gvw , 45,000 btu.
Tru-cool LPD 47391
40,000 gvw , 45,000 btu.
Tru-Cool Max. Twice the Cooling for Your Transmission. Maximum Protection for Your Vehicle. | Tru-Cool
When an auxiliary transmission oil cooler is required for your vehicle, Tru-Cool Max delivers optimal protection with double the cooling performance of our other products. Maintain lower temperatures in your transmission and lubricant with Tru-Cool and extend the life of the vehicle you depend on.
www.trucool.com
The cooler I have should be fine, once I tie in the radiator cooler. It's rated almost 3x the GVWR.
The big one is upside down! It needs to be flipped or mounted sideways and have the fluid pumped bottom to top. With it mounted like it is now only part of the cooler will fill with ATF.
The oe one must have some sort of valving in the input side to direct the fluid through all the tubes.
As yours is right now only a few tubes are getting fluid in them. The rest are empty.
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This is correct
You mean, how i plumbed mine? I did that so air would not be trapped limiting the cooling, and to prevent fluid drainback.
Yes. The cooler will be full. With it flipped it won't work well at all. I posted a pic from the manufacturer that shows how to mount one.
Blame Hayden (the manufacturer), it had no instructions with it. Funny that the trans shop owner didn't notice when i pointed out the cooler lines being easy to access. I honestly think he doesn't like me very much, based on how flakey he got. Once he had his money, I was just an annoyance despite the fact that he wanted me to bring it by for him to look at after we installed it.
I'll go straight to the nearest auto parts store 11mi away when i leave here next week, flip it over, and buy longer hoses for hooking it up. And I'll prefill the cooler so i can be sure it's full.
Report back with new temp readings
