i wouldn't say it's sucking it so to speak. it's just the way it's flowing and it has gravity on it's side so it just goes straight down and gets pulled through the lower hose back into the engine. doesn't give the radiator enough time to dissipate the heat as it flows through.

 

It has more to do with efficiency of heat dissipating thru a cross flow as opposed to downflow, couple that with high heat from transmission fluid, heat transfering to coolant, poor coolant system and you get the trouble your having.

 

I have a extra trans cooler on the drivers side of the rad, 12x8.

So I need an I/C rad and/or a baffle for the non-I/C rad and a shroud to cure the problem.

 

I had the same issues with my 90 727/307 4x4 it would always run way to hot . so I did the cross flow IC radiator change and it did make a huge differance ,but when towing it still got hot .Last week i had the trans rebuilt with a performance build ...HD parts and a much tighter converter .I tried not to tow with it because of the heating issue. But today I towed a good size load 17900 gcvw and it did fine, never got hot. But being a non lockup trans I knew it was back there

I did the baffle in the stock rad but was unhappy with the results the cross flow is somthing like 70% more efficiant

 

The trans is a rebuild Jasper trans, It really pounds into 3rd gear so I'm sure it's had the HD stuff put in it.......

 

The crossflow radiator will be better than the downflow, a shroud will be better than not having one. They all have the tranny cooler in front of the radiator. I would put another transmission cooler on it, one with a fan, at one time this was a dealer add on option. The non - OD trans. and no lockup converter is getting hot while towing at todays speedlimits, back in the day it was 65mph and that may have been ok for 3spd no OD and 3.07 gearing, maybe not... Your looking at a bundle of money here bud, even used parts that list is going to add up.

 

I can get a cross flow rad for $350 locally

Finding the I/C T-stat neck is a different story.

 

check out the radiator barn I paid under 300 for mine and I got the tstat housing for $30 on ebay. the stock tstat housing can be used by using 3 90 upper rad hoses and 2 pieces of pipe. thats what i did till i could find a housing on ebay and a fan shroud from a late 70s big block Dodge PU will work if you cant find a 91.5-93 shroud

 

That's great thanks..... Tony

 

Ok so I found 5-6 T-stat housings. They are all for 98+ 6bt will the 24 valve work or do I need the I/C 12 valve one?

 

you'll need a 12v housing. the flange on our 1st gens is on the side of the block. here's a thread with some pics to get an idea.... Replacing the Thermostat

 

Got it thanks.

 

Ill take a pick of what I did, I didnt buy a new thermo housing, I just got a 93 upper rad hose and some 1 1/2 sched 40 pipe and welded a 90 onto it. Not the prettiest but I drove for 5 hours in hot weather and never had a problem. Total cost was 23$ including the new hose.

 

Got it, cool... I was thinking exhaust pipe.