Cooling System Upgrade

[e21pilot]

My 92 extended cab 4.0V6/auto has always run a little on the hot side when towing. I plan to tow a lot this summer and was thinking of upgrading the original radiator. I don't see any evidence of leaks nor loss of coolant but it is old and I don't want any trouble on long trips.

I've replaced hoses, thermostat and a leaking water pump a few years ago and didn't see any noticeable improvement when towing.

I have the factory 2 row radiator which is aluminum with plastic tanks right now and wonder if there is a good quality exact fit 3 row radiator still on the market for the early Rangers.

 

[insaneranger]

I don't have a true drop in answer, but here's an option to consider if you can't find a factory style drop in radiator. Here's the one I'm using in my '88 extended cab V8 swap. It has two 1 inch cores & is 100% aluminum. It fits perfectly under the core support & is simple to mount. A 14" electric puller fan keeps mine running cool, but you can fit up to a 16" fan.

Northern Radiator | Muscle Car Radiators - 21 5/8 x 15 7/8 x 3 1/8

205138 Muscle Car Radiators - 21 5/8 x 15 7/8 x 3 1/8

www.northernradiator.com

 

[Blmpkn]

My vote is for a better fan considering it only runs "a little" on the hot side.

How are your trans temps while towing? Might want to look into an auxiliary cooler.

 

[gaz]

e21pilot:

This is what I did to keep the engine cool:

-I switched to the thickest auto transmission radiator made for an Explorer
-2 transmission oil coolers
-a remote engine oil filter and cooler
-removed the crank driven fan/clutch for an electric 16" thermal switch controlled puller fan
-160° Tstat with JET CHiP
-raised the rear of my hood ½" to help remove heat
-thermal jacket wrapped headers
-keep an eye on the fluids

No heat issues since.

 

[e21pilot]

Thanks for the tips. Sounds like a lot of serious thought and effort when into keeping your rigs cool.

I should have mentioned several years back I installed two explorer trans coolers in front of the rad after I burned up my second A4LD and that time, I got an upgraded A4LD from the rebuilder and have had no problems with the transmission since then. I didn't add a trans temp gauge so I don't know how hot it gets.

I only see the engine temp gauge creep up when towing and I turn on the heater in the cab to help with the cooling. I believe my Ranger came with the factory super cooling option which is probably why I have gotten almost 300K on the engine without any major issues despite all the towing I do.

I have the stock shroud and fan and replaced the clutch fan about three years ago. The temp gauge barley gets above the C mark when I am not towing -- even in the summer, so I know the cooling system still works OK. I am just pushing the limit on hauling.

I don't have much time for wrenching these days so I thought if I could find an upgraded 3/4 row rad that was a drop in fit, I could do it in an after noon and might get that extra 15-20% of cooling I need to make the difference. Just wondering if there is such a product out there now that parts for these older Rangers are getting more limited.

I should probably switch to a bigger truck but the Ranger is just the right size to get into tight spaces and it keeps running so I'll probably stick with it until I break it -- probably while I am towing!

 

[gaz]

e21pilot:

You could put an electric fan on each of your transmission coolers.

The way you setup your coolers can make some difference too. Mine are mounted so that the hottest fluid runs horizontally back and forth, while moving up, then does the same thing again in the next cooler.

If a fan with a temp sensor were installed on the second cooler and a manual on/off switch on your 1st cooler, I know you would experience a difference.

Thing is, your talking about engine oil temperature. For that, since you are using the crank shaft driven clutch fan, you could add a pusher fan to the front of your radiator. It could be either temp sensor activated or on a manual on/off. When your moving and towing it's on. That will make a difference!!

Believe it or not an engine oil cooler makes a big difference too. I had to routinely drive, in summer heat to Arizona and New Mexico from California, this is when I added the oil cooler and remote oil filter. That was all it ever needed to maintain during those increased heat conditions.

A remote engine oil filter alone can add close to a quart of oil to your system; more oil means better chance of cooling more. Using an oil cooler or an oil cooler with its own electric fan would just seal the deal.

The remote oil filter and cooler set up I have, run near 8 quarts. That adds A LOT OF EXTRA COOLING POTENTIAL to your engine.

Of course, changing from the stock 192°F Tstat to a 185°F or 180°F can help.