It all started after reading some not so good reviews on the 42RLE 4-speed Overdrive Automatic Transmission used from 2003 to present Jeep Wrangler and realizing heat is responsible for 90% of all transmission failures also compounded by larger tires. I picked up a Flex-a-Lite (made in USA) Heavy Duty Transmission Cooler off Ebay for $20 and did some Google search's for anyone running an aftermarket trans cooler on a TJ but not much was found online for this job so I spent a few weeks thinking about the mounting and finally decided a couple pieces of cold rolled steel mounted horizontally across the front V support was my best choice. Remember if you use the plastic tie mount things which come with the trans cooler you risk damaging your condenser and/or radiator because the constant bouncing when off-road will eventually damage the thin fins and core so it needs to be hard mounted. The fittings which came with the cooler did not fit my 2006 Wrangler factory cooler lines so I opted to just cut the lines and use hose couplings from Lowe's to connect to the short rubber flex lines. After removing the Fan, Shroud, coolant, Radiator, and loosening the AC Condenser, I was finally able to remove the V support so I could work on the mounting. As I removed the V support water poured out of the ends when I flipped it over so I drilled several small drain holes to prevent trapped water from rusting it out. Turns out the cooler built into the radiator is so tiny and cheap I just completely left it out of the loop which makes things much easier because you don't need to figure out which line is the cooler return, if your leaving the stock cooler in line the upper line on the trans is the cooler return. The 42RLE Series transmissions should only use AFT+4 Full Synthetic fluid at $5 a quart is now readily available in auto parts stores and much cheaper than dealerships. If you decide to change the trans fluid while your at it the factory specs call out 2 capacities for 42RLE, a dry fill of 8.8 Quarts or 8.3 Liters and service fill of 4 Quarts or 3.8 Liters, both capacities will vary depending on type and size of trans cooler used.
Parts
Flex-a-Lite TransLife Part #4120-20,000 GVW
4 10X24 X 1" Allen head bolts
4 10X24 X 1 1\4" Allen head bolts
3/8 Hose (included with cooler)
2 Hose couplers 3\8 Brass or steel
4 Adel Clamps #6 (Rubber Lined)
6 Hose Clamps (4 included with cooler)
2 Steel Pieces Cold Rolled 1\8 X 3\4 X 3 ft.
1 Gal. Prestone Dex-Cool (Extended Life Formula)
Optional
5 Quarts Valvoline ATF+4 (Full Synthetic)
1 Trans filter TF175 (42RLE)
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