Overheating Issues

[Jochen Woern]

Good day All.

So, I have been reading as well as researching this site for a long time now and I upgraded by 1996 Suburban based on the information I read here.

I have done the following mods:

- aFe Stage 2 Performance Air Intake Kit
- 4" inch Jerry Jardine, PINNACLE POWER EXHAUST with 5" inch Chrome Tip (Turbo Back)
- 2-1/2" inch Crossover Pipe, mandrel bent
- KENNEDY remote mounted PMD/FSD Cooler Package
- AUTOMETER Triple Gauge Pillar (Boost, EGT/Pyro, Trans. Temp.)
- HEATH Turbo-Master
- HEATH Max-E-Tork PCM

The Sub preforms AWESOME ever since I installed Bill Heath's upgrades. The Max-E-Tork and Turbo-Master really make this thing pull. Performance of the truck is great now, EGT's NEVER go above 1100 degrees and Transmission Temp is usually around 180 - 190 degrees. Runs as it should, pulls as it should and is a joy to drive now with the extra weight in the back.

BUT, I still notice overheating issues. The truck has not let me down yet, but it does become apparent that the Temperature Gauge does climb at times. This weekend the truck got so hot that the Coolant ran out of the overflow hose on the Coolant tank/reservoir. The Temp. Gauge was NEVER close to the RED Zone, nor did any warning lights come on, but the Gauge was 3/4's up showing approx. 230 degrees. Once I pulled into camp, I could really hear the water bubble inside the tank. I filled the truck back up with Anti Freeze (I lost approx. 3/4 of a Gallon) the next morning and made the trip home with no issues and no further leaks (Going mostly down hill instead of going up).

My question to all of you now is the following:

- Is an INTERCOOLER the ONLY way to stop this thing from overheating?
- Will a bigger fan/a different fan clutch altready do the trick?

I really want this Truck to be reliable, I want it to run for as long and as hard as I should possibly be able to push it (keeping EGT's of course in mind) and I do not want to have to worry about the darn thing getting hot. (The Northern CA Heat of 100 degrees certainly does not help either).

ANY SUGGESTIONS on what to do?

Thanks in advance.

[DennisG01]

No, an IC is not the only way - especially as you're not pulling a whole lot of weight. Before my 18:1, I was towing a boat that weighed in the same neighborhood as your trailer. I never had overheating problems. I had results similar to you on my EGT gauge, as well.

-- Does your '96 have the dual T-stat crossover? If not, get it.
-- I've had good results with "Red Line Water Wetter". Nothing to set the world on fire, but it did help.
-- Have you cleaned in between the radiator and other stuff up front?

A new fan is not needed if you already have the 9-blade steel fan. An HD fan clutch from Kennedy could help, but based on the weight you're pulling, I'd put that way down on the list.

[Jochen Woern]

- YES, I do have the dual thermostats on my rig.
- YES, I have cleaned out all the goop in the front which accumulates on the bottom of the radiator.
- I do have the original 5 blade fan.

- "Red Line Water Wetter" ????, I am not familiar with this at all, could you please describe in detail.

Please also do not forget that the dry weight of my trailer is not what I am towing, if the trailer is loaded and the water is in the tank (Plus all the Beer one drinks during a Camp Trip :), I am guessing that I am pulling close to 8500 pounds.

[rameye]

sounds a little suspect...I would suggest testing the radiator cap!

[Jochen Woern]

The Overflow Reservoir including Cap is fairly new, installed approx. 11 month ago.

There is NO Radiator Cap on the 6.5, the Cap is holding the pressure in the reservoir/tank.

ANYONE ELSE WHO COULD POSSIBLY HELP ME OUT HERE PLEASE?

[DmaxMaverick]

"Radiator Cap" is a dated nomenclature, and really doesn't mean a traditional radiator cap, specifically. If your truck doesn't have one, then the reservoir cap, or "coolant system pressure cap" is meant. It should be tested, as should the cooling system. A leaking cap, or pressure loss of the system will be a good diagnostic step.

[Mark Rinker]

New radiator. Cheap investment, and will provide MAX cooling over older with possible blocked passages and deposits minimizing performance.
New Kennedy fan clutch. HUGE difference in cooling effect with the stock fan blades.I put a stock OEM replacement radiator in, but had considered/priced out a 4-core custom made at our local truck radiator shop. Increasing coolant capacity can't go wrong, but I don't think its necessary - a full flowing OEM equivalent should work find if you have lots of air flowing over it, unrestricted.


These two should do the trick. Had all your same mods, same 'moderate' overheating, and solved it with the two mods above...

[Jochen Woern]

Thanks very much everyone.

[DennisG01]

Link to Water Wetter:
http://www.redlineoil.com/products_coolant.asp

[16gaSxS]

you can try to do it piece meal or the whole works. Upgraded cooling to the 97 set up and the Kennedy fan clutch. If you change the water pump you might as well do the timing gears and chain since it lives behind the water pump and you have 80% of the labor done already. If I would do it on a 12 year old truck would depend on how long I planned on keeping it.

[Jochen Woern]

What are the '97 Cooling Mods? What is different other then the dual thermostats which I have?

Thanks.

[DennisG01]

Unless I'm missing something, I think the only thing you're missing is the 9-blade fan.