I've got a 1999 5.4L Expy without the tow package. Have a Class III Hitch for the occassional towing I do a few times a year. Going to be moving over to North Carolina from Texas and planning to pull a 6x12 U-Haul with the Expy. With the long haul (and realizing that the 5.4L heavy duty cooling does not include tranny cooler without towing package option) I want to install a tranny cooler. Can someone give me instructions on where it ties in and do I need any special fittings, etc. than what I can expect with a standard cooler kit? I see the two lines coming from the tranny to the radiator - one to the upper and one to the lower driver side, but how exactly does this tie to a tranny air cooler in before I buy a kit - does it completely bypass or tie in series?

Also, If anyone has comments on towing with the 5.4L and the 4R100, I'd love to hear them - I have 109k on the truck and about 75k on the tranny (had a rebuild at 35k due to issues). Just tuned up the truck - coil packs, plugs, going to do front end, and my only concern is if a 4R100 that old is up to it.

Thanks,
JLD

 

How heavy will the trailer/cargo be?

 

Standard U-haul 6x12 loaded up - I expect gross trailer weight loaded around 4500 lbs. and I'll have some gear in the truck too. I don't expect it to be a problem - I typically tow an older 18' hydra sports center console on 60-70 mile trips and that is probably around 4000-4500 lbs. and I occassionally tow a 26' offshore rig on very short trips and that weighs about 8500 lbs - these are all in flat terrian.

My concern is more on the distance and the fact that there will be some short hills to climb with the age of this tranny. It was rebuilt at 35k miles and have flushed it every 30k miles or so since. It exhibits no problems other than the bucking at 45-50mph, but I think I knocked this out over the weekend by going through the coil packs, testing them (resistance), changing worn boots, and new conductors. Still testing, but the issue seems to have gone away. Now I'd feel much better knowing how to install a cooler and hearing of people who are towing long distances at this mileage with no issues.

Thanks to all in advance.

 

Are you sure yours doesn't have the tranny oil cooler? My 03 has the class III with the aux tranny cooler. Follow your tranny oil lines up to the front and if they go to a radiator type unit I think that's your oil cooler. I wouldn't worry about it any since you are within your weight limits plus if you're a patient driver you can drive with the overdrive off in the hills.

 

Nope, no tranny cooler. I didn't order the tow package when I ordered my Expy. The hitch I have is an aftermarket add-on. I see the lines coming from the tranny into the main radiator (one goes to the upper driver side, other to lower). Just want to know how I tap in and if I need to cut anything - looks like these are all threaded/flared fittings and not sure how to tap into, bypass existing raidiator, etc.

Even though I'm within the weight limit, I'd still feel better with the cooler - figured the extra protection is well worth the few extra $$$. I'll be driving 60-65mph w/o overdrive on this trip and it's 1100 miles.

 

Disconnect the lines, plug the threaded holes in your radiator and route the lines to the new cooler you install in front of your radiator. You'll probably have to cut the lines and add a piece of rubber tubing to make the final connections.

 

Why bypass the radiator? You would just be taking more cooling area away. just piggyback from the radiator to the new tranny cooler and back out to the tranny. if your looking for a cooler there's alot of guys in the 7.3 diesel forum that are swapping out there stock coolers for ones off the 6.0's. I bet if you offer to pay shipping somebody will send you there old one that would work great for what you are going to be putting it on. You will have to get a couple of fittings and hose. Eather that or check EBAY. Good Luck.

Hook

 

Thanks for everyone's comments. I finished the job today on my '99 5.4L and thought I'd post the steps since I haven't seen much in searches on the exact install. I installed a Hayden 'Ultra Cool Heavy Duty' air cooler. It's 10"x15"x3/4" and I picked it up at O'Reilly Auto Parts for about $40. I also picked up the Hayden Ford fitting kit for $12 (two brass fittings - one male that goes into the radiator and one female that goes onto the return line). I also picked up some tie wraps, an extra 4' of tranny oil cooler hose, and extra hose clamps (I like to double clamp these things).

Take the black plastic trim piece (the one with the fan routing/emissions sticker on it) off and then you can get to the a/c condensor radiator and use the included mounting straps and foam blocks to secure the cooler to the condensor/radiator. I mounted mine on the driver side a little left of flush to allow room for hoses. Note that you may want to put the hoses on before mounting the cooler - I didn't and have a few cuts on my hand to show for it.

One you have the cooler in place and the hose (I used two 4' sections of tranny oil cooler hose with double clamps), you can get to work on disconnecting the tranny lines on the radiator - these are on the driver side of the radiator and there is an upper line and lower line. I took of the intake to give me room to work. I also disconnected the small vent line from the top of the radiator to the coolant overflow tank.

I put a oil pan underneath to catch the fluid that dripped out - I lost less than 1/2 quart. While underneath, I also removed a small metal clip that holds the two tranny lines together forward of the oil pan. I then removed the upper line to give more working room and then removed the lower line. I used a 16mm open end on the line fitting and a 1 1/16" open end as backup on the brass fitting that the tranny line fitting sits in at the radiator. Once you get the lines off, time to put the new cooler in line (in series with the radiator).

I took the male brass fitting from the fitting kit and put high-temp teflon tape on it and snugged it in the radiator lower opening with a 3/4" deep socket. Then take the female brass fitting from the fitting kit and snug it to the line/fitting that you disconnected from the lower radiator. You'll need a 3/4" open end and a 16mm to tighten these together - don't forget the high-temp teflon tape again.

Next, route and test fit the hoses, cut to length, and put two hose clamps on each. I attached the upper line from the cooler to the radiator and the the lower line on the cooler to the return line that you disconnected from the radiator.

Put everything else back together, start the car, run for a couple of minutes, check for leaks, check that you have heat after a couple of minutes on the new hoses to make sure you have flow, and check to see if you need to top off the fluid.

That was it - fairly easy with the right tools, wish I would have done it sooner, but feeling good about pulling the uhaul on the 1100 mile trip with the Expy now that it's done. Going to go this week and get a tranny flush at the dealer (and my cruise control recall) since I'm due.

Jacques