Cooler question

*svt4cam* · 11-09-2009, 02:22 PM

Ok I ordered my reman trans 5r55e from Jasper today for a 2000 xlt 4x4 4.0 sohc. I'm hesitant to continue using the radiator as a cooler/heater I thought I caught a whiff of antifreeze smell as I was pouring off the lube from the old trans, could be wrong it looked alright no pink crud. Anyways can I bypass the radiator cooler and just use the auxilary cooler mounted in front of my radiator after cleaning it and the lines out and installing a remote filter? Would that provide sufficient cooling if I'm not doing any towing?

Thanks Steve

**Maniak** · 11-09-2009, 03:31 PM

Most external coolers are aux. coolers. Meaning they can't cool the fluid enough, especially at lower speeds.

Also, keep in mind that the radiator cooler is also a heater. In Winter it will warm up the fluid.

There are some external coolers big enough to keep the trans cool but I don't think I would "only" run that type of cooler in NJ as you will need to get the cooler up to temp in the winter. I "guess" you could get one of those thermo bypass units which would try to get the fluid up to temp before it would let it go through the cooler. All the ones I have found are around 180F.

Just for comparison, I am using a 45,000 BTU (40k GVWR) 11x22x1.5 cooler on a c6 transmission in a heavy vehicle (the 3/4 4x4 van). The highest temp I saw while pulling uphill at 60mph in 3rd gear on a non lockup converter was 165F in the pan. It was around 90F when doing that. In general that cooler is keeping the fluid about 50F above ambient. It will climb some under a heavy load (its a non lockup transmission).

If you were to use that cooler, and it was close enough to the radiator for air to be pulled through it at the lower speeds, it should keep your trans cool, but I still think it would be too cool in winter.

~Mark

*2000StreetRod* · 11-09-2009, 06:32 PM

I've read that the 5R55E has internal ATF temperature control although I have not been able to confirm it. Supposedly, external ATF flow is prevented when the internal temperature is within operating limits. That's why I was not concerned about not using the radiator cooler to heat my ATF (I use it for engine oil). As of this fall, I have two of the stock external coolers after a remote filter. To date I have yet to see the external ATF temperature reach my gauge minimum reading of 100 degrees. See the link in my signature for a lengthy thread on my oil cooling system.

11-09-2009, 02:22 PM	#1
svt4cam Elite Explorer The Wilds of New Jersey 00 XLT, 02 Sport, 03 XLT Join Date: Sep 2009 Posts: 93 Vehicle Specs (Original Poster)	Cooler question Ok I ordered my reman trans 5r55e from Jasper today for a 2000 xlt 4x4 4.0 sohc. I'm hesitant to continue using the radiator as a cooler/heater I thought I caught a whiff of antifreeze smell as I was pouring off the lube from the old trans, could be wrong it looked alright no pink crud. Anyways can I bypass the radiator cooler and just use the auxilary cooler mounted in front of my radiator after cleaning it and the lines out and installing a remote filter? Would that provide sufficient cooling if I'm not doing any towing? Thanks Steve

11-09-2009, 03:31 PM	#2
Maniak Moderator-Stock 91-94 Vail, Arizona 1992 XLT 4x4 Join Date: Feb 1999 Posts: 10,748 Vehicle Specs	Most external coolers are aux. coolers. Meaning they can't cool the fluid enough, especially at lower speeds. Also, keep in mind that the radiator cooler is also a heater. In Winter it will warm up the fluid. There are some external coolers big enough to keep the trans cool but I don't think I would "only" run that type of cooler in NJ as you will need to get the cooler up to temp in the winter. I "guess" you could get one of those thermo bypass units which would try to get the fluid up to temp before it would let it go through the cooler. All the ones I have found are around 180F. Just for comparison, I am using a 45,000 BTU (40k GVWR) 11x22x1.5 cooler on a c6 transmission in a heavy vehicle (the 3/4 4x4 van). The highest temp I saw while pulling uphill at 60mph in 3rd gear on a non lockup converter was 165F in the pan. It was around 90F when doing that. In general that cooler is keeping the fluid about 50F above ambient. It will climb some under a heavy load (its a non lockup transmission). If you were to use that cooler, and it was close enough to the radiator for air to be pulled through it at the lower speeds, it should keep your trans cool, but I still think it would be too cool in winter. ~Mark __________________ Click HERE to see our Explorer Specs

11-09-2009, 06:32 PM	#3
2000StreetRod Elite Explorer Greenville, SC 2000 Sport SOHC 2WD Join Date: May 2009 Posts: 5,577 Vehicle Specs	internal control I've read that the 5R55E has internal ATF temperature control although I have not been able to confirm it. Supposedly, external ATF flow is prevented when the internal temperature is within operating limits. That's why I was not concerned about not using the radiator cooler to heat my ATF (I use it for engine oil). As of this fall, I have two of the stock external coolers after a remote filter. To date I have yet to see the external ATF temperature reach my gauge minimum reading of 100 degrees. See the link in my signature for a lengthy thread on my oil cooling system. __________________ My Helpful Threads, Registry, 16.4/23 mpg, 3900 lbs, 5R55E, 3.73:1, 175 rwhp, Henson custom tune, CAI, Spectre air filter, Lightning 90mm MAF, 75mm throttle body, A/F ratio meter, synthetic oils, Accusump, 2 row radiator, 3+1 leaf springs, .75 inch drop, Edelbrock IAS lowering shocks, engine oil & ATF temp gauge & remote filters & coolers, remote crank