ok guys i just bought a 97 1 ton with 28k miles on it. I am thinking about intercooling it to keep the temp down under heavy loads. one of my concerns is how to run the piping around the fan. Im considering removing the stock fan and putting electric fans in to replace it but i need to know the flow rating of the stock fan, i think the duramax is around 1200 cfm and i have read that one of the mods for this truck is to run the duramax fan. if anyone has run electric fans and could give me some input on how to go about it please let me know.

Welcome to the Place, fILL IN THE SIG INFO ON YOUR TRUCK. One post here states electric fans are ineffective overall. Save yourself some time & just get a JK severe duty fan clutch.JK also touts the 9 blade,steel 20 inch fan blade from a 99/2000 3500 truck. The Duramax composite blade is superior engineering,IMO & I prefer 180 T stats ,also available from JK. PS,The DPage currently has an article,complete with pics & parts supply info, on a DIY intercooler for about $400.00.Do all this now & add miles & years of life to the new truck. Cooling improvements on the 6.5 is VERY important.

Welcome to the Place :welcome2:

First order of business is filling out your signature we help us help you post to post. Follow info in my or other 6.5 Mods signature.

2nd order of business go thru FAQ stickies locked above the general forum area in it is most of the basic 6.5 stuff is in that thread.

97 has h/o water pump from factory, search for threads on radiator/raditor cleaning (this is well covered ground here) THE MOST IMPORTANT THING when it comes to 6.5 cooling is spotlessly clean ac core & radiator, along with dirt/bug free oil & trans coolers regardless which fan/clutch combo you wind up with, electric fan kits currently available do not surpass cooling capability of a mech fan,

What TD said. Fill out your signature to tell us about your truck.

You already have the 1997 cooling mods, which means the dual thermostats, the high capacity water pump, etc. As Turbine Doc indicated, you will need to check your radiator to make sure it is scrupulously clean, especially in between the coolers (in most cases, the only way to tell is to pull the grille, the upper fan shroud, etc ... which means you already have it almost all the way out. As it happens, pulling the rad all the way out is the only way to make sure you clean it properly anyway, so I suggest you pull it and clean it just as a matter of basic maintenance.

Note we're talking EXTERNAL cleaning ... in the fins, between the coolers, etc. Internal cleaning is a whole 'nother deal.

Fan clutch: get a re-tuned (early-engaging) severe-duty fan clutch from a diesel vendor. Heath has 'em, as does Kennedy, Hayden, SSDiesel, and others. DO NOT buy one unless the vendor can guarantee you it will kick in 10-15* earlier than 212*F. The Duramax composite fan is the best fan for these trucks IF your current fan is centred in the shroud (check before you pull things apart). If it isn't centred, be prepared to trim your shroud (NOT your new fan) to make it fit.

Electric fans don't work as well, although they make running an intercooler easier. DieselPlace member WildWilly had a great e-fan and IC setup, and can tell you why he switched back to the mech. fan.

There are several intercooler threads on here... a few of the more recent ones are:

Dave12 posted one with pics of his hanging ATA
ChrisK1500 posted one with pics of his WTA experiment
ScrufDog posted one with pics of his Hood-mounted IC

Use the Search function to find more... Search is your friend!


Listen to the mods - Turbine Doc has an nice IC setup and pulls heavy with no issues. He and the other guys all know this stuff inside-out from having been there and done that...

And congrats on your truck... a 97 3500 F with only 28K on it? Nice!

my truck was a plow truck for its whole life, this is the first time it has been titled, the only thing they did was plow a parking lot with it but all and all they took pretty good care of it.

If that's all it did, then your rad is likely fairly clean on the outside. If they did their maintanance, and changed out the coolant every so often, if might be fine INside, too.

But I wouldn't bet the farm on the fan clutch... it is 10 yrs old, and they do degrade. In any case, I would first try it out with heavy loads before I started worrying about replacing things... does it overheat?

More pressing would be getting the new exhaust on (I hope you're changing the downpipe, while you're at it), doing gauges (EGT and Boost, at least), and then putting a reflashed PCM in it.

Rules of thumb: (in more-or-less order, depending on application)

1] make sure it can breathe (air in, exhaust out)
2] safety first (gauges let you know when things are wonky), PMD Isolator for reliability, oil cooler lines if leaky
3] add fuel, tranny line pressure, change injection curve (reflashed PCM)
4] cooling/intercooling mods to protect engine from heat damage
5] maintenance as required (injectors at 100K, glowplugs as needed, balancer when inspection says so (they degrade, too - mileage doesn't matter, but age and environment does)

Post pics. Brag. Ask for help. Contribute to the knowledge base and the community.

Welcome aboard!

a 97 with ONLY 28k miles? Holy mackrel! :eek: The thing is brand new!

As far as your mods, I'd hold off right now. The first thing I'd do is relocate your PMD (It is a module on the injector pump.) The injector pump is mounted under the intake manifold, and the heat destroys this module. Do a search on PMD and do some reading. If it fails, you don't go anywhere.

Next, I'd flush the coolant and get rid of the Dexcool, cause it turns to mud after awhile and plugs everything. Use regular Prestone.

Next, go through and clean EVERY ground. Search the posts here for one that tells you where all of them are.

The 6.5 tows, but it is not the optimum engine for doing so. Stock reliability is not GREAT, but thanks to the people here and on other forums, they have got this engine up to the point that it is quite usable and dependable. Do alot of reading here. Educate yourself on this engine, and it will last a long time. Keep it stock and do the wrong things, and it will be the most expensive headache you ever had.

I'd work on taking care of the PMD before doing cooling mods.

http://img.photobucket.com/albums/v475/gsrintegra175/PDC_0171.jpg
http://img.photobucket.com/albums/v475/gsrintegra175/PDC_0173.jpg

today i changed the fuel filter, oil, added diesel klean, ordered new tranny cooler lines, and started to work on my rats nest of plow light wires... does anyone know where you usually splice in to hook up the plow lights? right now i cant switch back to the truck lights and only 1 low beam light works...

Oke doke, it has a cooler (But not mounted in a good place)

I would think it is connected up front on the harness? That is where I normally get the light wires for a plow. Find the wires that go to the plow, and trace them back.

Before you get too crazy in troubleshooting, make sure the lights just aren''t burned out. They may have used the lights on the plow and neglected the head lights on dedicated trucks.

can anyone find me a fuse panel diagram? i dont know what fuses are for what, i have no horn and no wipers but the wipers are probably the circuit board problem...

whew, plow lighting can be a pain in the ass, if the first installer didnt do it right. nice looking truck btw.

can anyone find me a fuse panel diagram? i dont know what fuses are for what, i have no horn and no wipers but the wipers are probably the circuit board problem...

Start by checking fuses individually. You see one blown, change it. Be ready with spares, if it blew once, it may do it again, unless you peg root cause.

Holy rust lord!

How did that thing get so rusty with such low miles? The engine looks like it has been sitting in a field for 20 years!

Holy rust lord!

How did that thing get so rusty with such low miles? The engine looks like it has been sitting in a field for 20 years!


He said it spent life until now as a plow truck so I expect a lot of that corrosion is chemically induced from de-icer chemicals

Gonna need some catch up work to clean up a bunch of grounds and things with that amount of rust and corrosion too. If they are not problematic yet, they will be.

I also use my truck for plowing some snow. For some reason that darn plow produces a vacume between it and the grill. Any and all salt that is kicked up from the front wheels gets sucked up and into the grill and then right into the engine compartment. Others who have a plow on their truck will know what I mean.