[Heath]

Excellent write up. Only thing I would do different is connecting that ground to thicker metal so you can tighten it more. Grounded to sheet metal with s self tapping screw always eventually works loose at the worst time.

[Jerry Bransford]

Originally Posted by Heath

Excellent write up. Only thing I would do different is connecting that ground to thicker metal so you can tighten it more. Grounded to sheet metal with s self tapping screw always eventually works loose at the worst time.

I see your point though at that particular location, there is a double-layer of sheet metal which took some doing to get the self-tapping screw to thread into after drilling the hole. It is much more secure than most sheet metal screws I've used for electrical connections in the past.

[grogie]

Excellent write-up! This is another project on my list as I intend to tow a small trailer. Thanks Jerry... good timing.

[Heath]

Originally Posted by Jerry Bransford

I see your point though at that particular location, there is a double-layer of sheet metal which took some doing to get the self-tapping screw to thread into after drilling the hole. It is much more secure than most sheet metal screws I've used for electrical connections in the past.

Cool

[dirtycruiser]

Great write up! I had just ordered my cooler kit that mounts in front of the radiator, days before I saw this. But I'd be afraid of rocks and water killing the fan, ( I know I would forget to turn off the switch if I had one) since we get into quite a lot of water holes down here in SW Florida. Also I just serviced my trans at 31,000 miles, replaced my stock trans pan with the mopar larger version, I did have a few nice dents in the stock one. My new trans and oil pan skid is due in tomorrow. ( my trans pan is also 21" off the ground)
What do you think of the Derale Performance "Heat Sink" Transmission Coolers ? would it be overkill to add one of those in line along with the other coolers?

[SideshowBob024]

Originally Posted by Knuckelhead

Yes I do and it works well for my setup.

I also have an indicator light next to the transmission temperature gauge to let me know when the B&M transmission cooling fan kicks in at a known temperature (I have an adjustable rheostat installed on the B&M fan), one sending unit on the transmission output line for the temperature gauge...

*copies down furiously. Nice setup.

[parcours]

Going back to the question regarding the SWB vs LWB.

Will this cooling setup work on an 2005 Unlimited? Are the lines long enough to place the cooler/fan unit just behind the trans skid plate?

Also on my '05, the trans cooler radiator connections are flanged metal tubing, how do you remove the plastic connector into the radiator and connect it to the Derale hose?

[Unlimited04]

Originally Posted by parcours

Also on my '05, the trans cooler radiator connections are flanged metal tubing, how do you remove the plastic connector into the radiator and connect it to the Derale hose?

the tranny hoses are a different design. you should be able to use brass junctions

[Yucca-man]

Originally Posted by parcours

Going back to the question regarding the SWB vs LWB.

Will this cooling setup work on an 2005 Unlimited? Are the lines long enough to place the cooler/fan unit just behind the trans skid plate?

The answer I got (Page 1?) was that while it should fit, there isn't the same protection because the control arm mount is farther back on the LJ.

[commodore_dude]

Now that I've seen this kit - http://www.quadratec.com/products/56112_3101.htm - I'm wondering what the pros and cons are compared to the Derale kit. I know you mentioned adding a power steering cooler Jerry, is there any reason you decided against this PSC kit, since it has both? For us LJ folks it would also solve the concerns around line length and protection for the Derale cooler...

[robncar]

Originally Posted by commodore_dude

Now that I've seen this kit - http://www.quadratec.com/products/56112_3101.htm - I'm wondering what the pros and cons are compared to the Derale kit. I know you mentioned adding a power steering cooler Jerry, is there any reason you decided against this PSC kit, since it has both? For us LJ folks it would also solve the concerns around line length and protection for the Derale cooler...

No electric fans and adding the heat load to the coolant radiator, I would think. Perhaps, it would be fine with the 9/10 blade fan and clutch upgrade though.

[Unlimited04]

FYI - for those plumbing up a 42RLE tranny cooler...

The hot side is the lower line on the drivers side of the tranny - it's connected to the passenger side of the radiator.

The cold side (return to tranny) is on the upper drivers side of the tranny - it's connected to the drivers side of the radiator.

This was pointed out to me by another member on here (with an 06), and I verified it on my 04.



This shows the tranny fluid which normally would be routed to the passenger side of the radiator - this is the hot output of the transmission.

So...my junk is actually plumbed wrong, and I've been advising people wrong for a few years . dang it. and jerry, if i'm reading your write up correctly...you plumbed yours the same way I did, and we're both cooling the fluid before it enters the radiator, since the passenger side is not the return line, it is the inlet line.

The correct cooler plumbing should look like this:


so...might want to check how you plumbed your 42RLE cooler.

[robncar]

Originally Posted by Unlimited04

FYI - for those plumbing up a 42RLE tranny cooler...

The hot side is the lower line on the drivers side of the tranny - it's connected to the passenger side of the radiator.

The cold side (return to tranny) is on the upper drivers side of the tranny - it's connected to the drivers side of the radiator.

This was pointed out to me by another member on here (with an 06), and I verified it on my 04.

This shows the tranny fluid which normally would be routed to the passenger side of the radiator - this is the hot output of the transmission.

So...my junk is actually plumbed wrong, and I've been advising people wrong for a few years . damn it. and jerry, if i'm reading your write up correctly...you plumbed yours the same way I did, and you're cooling the fluid before it enters the radiator, since the passenger side is not the return line, it is the inlet line.

The correct cooler plumbing should look like this:

so...might want to check how you plumbed your 42RLE cooler.

Interesting! I determined the hot line with the "hand test" on my '05. I put the inductive temperature sensor on the "hot" line (bottom) and the aux cooler/filter on the "cold" line (top)... well, at least I think I did. I'll verify that when I get a chance.

Sent from DROID2

[Unlimited04]

Originally Posted by robncar

Interesting! I determined the hot line with the "hand test" on my '05. I put the inductive temperature sensor on the "hot" line (bottom) and the aux cooler/filter on the "cold" line (top)... well, at least I think I did. I'll verify that when I get a chance.

Sent from DROID2

yup, i did the inductive method & used an IR temp gun before, and it gave me the wrong answer.

the diagram shown above is correct - upper hard line is back to tranny from cooler, lower hard line is hot out to cooler.

and the hard lines do some gymnastics getting up toward the crank pulley, so make sure you follow them closely to match up where they go to the radiator.

this also explains why my inline trans temp gauge doesn't see much above 160°F - it's reading the cold side back to the tranny . I'll be replumbing my junk this weekend and reinstalling the temp sensor in the "true" hot side line.

For those looking for a cheaper junkyard alternative to this Derale...



Biggest tranny cooler I could find in the junkyard off a truck (12" x 12" or so) and a Denso pusher electric fan off a late 1990s Land Rover. The fan is only two wires - power and ground, and the mounting thickness is 2". Fab up some brackets to make it all fit and hook the fan to a relay & thermal switch or toggle switch, and you've got a low cost option. This Land Rover fan runs $330 ea in the aftermarket and ~$32 for two at the junkyard.

[Heath]

It's a rover. It will most likely die one you at the worst possible time. j/k