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Topic: Transmission Cooler Questions (Read 758 times) previous topic - next topic

Transmission Cooler Questions

Looking at my transmission cooler's rusted exterior I have terrifying thoughts about things failing internally and the coolant and trans fluid mixing.  I was looking for anecodtes from people who:

Lost a trans cooler and had coolant and trans fluid mix.  How bad and costly was the damage in real dollars?

Has anyone replaced a trans cooler as preventative maintenance?  This idea looks less and less absurd to me every day and it looks really easy to get out.  I wonder what the heat exchanger costs though.  Hopefully less than $1K.

Re: Transmission Cooler Questions

Reply #1 –
Check Roland's old posts. His failed and the coolant mixed with tranny fluid. Bad cocktail.

Failed Transmission cooler

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Transmission Cooler Questions

Reply #2 –
The trans cooler works the same as an engine oil cooler. If you keep your coolant maintained there will not be corrosion internally. The only failures I have encountered were when coolant did not have rust inhibitors or proper mix of glycol.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Transmission Cooler Questions

Reply #3 –
Not all of us have maintenance records for coolant type or when it was changed by the previous owner(s). Since we drive diesel pushers, winter road spray may also effect the longevity of the cooler. Also, all Foretravels don't have the same design, materials or location of the cooler. Good to contact Roland for the coach maintenance history, mileage, cost of repair, etc.

An air to air cooler could be fitted with fan. This would be much like a turbo intercooler but smaller. With the transmission in lockup, there is not that much heat generated since there is no torque converter slippage. Our transmission temperature is far higher in city driving where we we get a lot of start and stop cycles in first and lower second gear.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Transmission Cooler Questions

Reply #4 –
When there is surface rust on tranny cooler, we recommend spraying with Loctite Extend rust protector.  We us Extend on oil pan and all metal with surface rust.  Do not remove surface rust prior to spraying Extend.

Re: Transmission Cooler Questions

Reply #5 –
Quote from: Barry & Cindy –
When there is surface rust on tranny cooler, we recommend spraying with Loctite Extend rust protector.  We us Extend on oil pan and all metal with surface rust.  Do not remove surface rust prior to spraying Extend.

Thanks I have a can of that.  I'll add it to my list.

Re: Transmission Cooler Questions

Reply #6 –
Quote from: Barry & Cindy –
When there is surface rust on tranny cooler, we recommend spraying with Loctite Extend rust protector.  We us Extend on oil pan and all metal with surface rust.  Do not remove surface rust prior to spraying Extend.
Would Corrosion X do any good for removing the surface rust and sealing the surface prior to Extend?
 
Trent
Trent and Jean Eyler
2000  U295  4003  WTFE  ISC  350
Build#5603 MC#17385

Re: Transmission Cooler Questions

Reply #7 –
Another great and dirt cheap product that I have been using on rust is OSPHO or POR15. Just spray on and let dry then paint away.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Transmission Cooler Questions

Reply #8 –
A $20 HF handheld spot blaster filled with soda will clean it like new, washes off without residue and then can be painted with the user's favorite. The onboard air compressor will supply enough PSI/CFMs to do the job on this small part. Filled with soda, it can be used around mechanical/electrical devices without fear of contamination like sand would do.

21 Oz. Hopper Gravity Feed Spot Blaster Gun

50 lbs of soda: Soda Blasting Media - 50 Lbs. Medium Grade

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)
 

Re: Transmission Cooler Questions

Reply #9 –
Extend only works on rust and stops rust.  Spraying CorrosionX negates Extend.