Intercooler for the 6.5 Diesel Engine?

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

Is an innercooler available for the 6.5?  If so, how much gain in horsepower could be achieved by such installation, and at what cost for the installation? Thanks, Will M.


Should Their Be Metal Sleeves for Control Arm Bushings on My '99 Suburban?

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

I have a ‘99 2500 Suburban, when I replaced the lower control arm bushings the replacement bushings had a metal sleeve, however the originals had no metal sleeves. I took the control arms to the dealership and even their head suspension mechanic had no answers.  I ended up buying new complete lower control arms and they also had sleeveless bushings.  Can anyone tell me why everywhere, including the Chevy dealership, only sold sleeved bushings.  I was told I left the bushing sleeves in the control arms.  However the old ones don’t have any and the new replacements didn’t have any.  Any help on this would be greatly appreciated!


How Do I Determine If I Need to Rebuild My Turbo?

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

I have a 1986 K30 regular cab. It has a 6.2L diesel. Mileage is about 110,000. I have purchased a used Banks turbo kit that was designed for the 6.2. My question is how to determine if the turbo needs rebuilt prior to installation in my truck. Is there a maximum amount of play in the shaft that I can measure? I.e. max amount the end of the shaft should moved when pushed in a radial direction, as pushing towards the circumference of the opening? How about max amount of play pushing the shaft in or pulling it out along the shafts axis? I have tried taking it in to local shops which rebuild turbos and also calling Banks but have not found any definitive answers. Thanks, Mark W.


1998 6.5 Engine Runs Well at High RPM but Smokes at Lower RPM

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

Hi there. I love the magazine! I have a 1998 GMC 1500 Z71 Sierra extended cab 4x4 6.5 automatic. It has 170,000 miles on it. Engine codes are P0236,P1409,P1653,P0401,P400. I have installed new CDR valve, Vacuum pump, Wastegate Solenoid Valve and both EGR Solenoids. It bellows black smoke with no power until the rpms come up and the boost. Then it runs pretty good until I slow down . If I unplug the vacuum line to the EGR and cap it off it runs fine with no smoke at all but then the check engine light comes on. I have to get through emissions so I can keep my truck registered. Any help would be great, thanks. Kurt B. – CT


Setting Code 78 and Heavy Black Smoke

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

I have been having a problem with my 1995 GMC 3500 HD dump truck and maybe you will be able to help me out. For some time now, my truck has been having a service engine light. I had it checked and find that it is setting a code # 78. When it does this, it also smokes heavy, black smoke. Our Chevy dealer checked it out and replaced the boost sensor on the top of the engine. However, this repair did not fix the problem and he tells me he is stumped. A mechanic friend suggested that it was a bad vacuum valve and that we ought to tie the boost lever with wire to hold it closed. The truck no longer smokes, but it still turns on the service engine light and sets code #78. So now, I don’t know what to think about this problem. Is it too much boost or too little? We seem to be out of options. Can you help?


1996 6.5L Radiator Gets Too Hot When I Idle

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

I’ve got a cooling issue with my '96 6.5. I have cleaned the radiator and other coolers and even put on a new fan clutch but when pulling a load especially at low speeds the engine will run at 210 or just over. If I let it set and idle or high idle with the A/C on it will run up to 220 and you have to drive down the road to cool it off. Never had it flushed and it still has the single stat setup. I do have the dual stat setup but after reading the last issue am not sure which is the best route to go.


Dash Rattles and Windshield Mounting Screws are Cracking Out

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

I have a '95 extra cab ¾-ton 4x4 6.5 Chev truck and now , thanks to your fine magazine and the solutions it has guided me to: it runs great and I really like it. Now I have another issue for you: my dash rattles and I can see that the mounting screws that run along by the windshield are cracking out: the plastic is broken where the screws go in. Is it just me, am I the only one with this problem or is there some way to fix it without having to replace the whole dash? John C. – Turlock, CA


1997 6.5 Burns More Oil on Local Trips

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

I have watched it carefully for years now and find that my 1997 6.5 GMC one-ton uses more oil when I am driving locally than it does when I tow my horses on long trips. This makes no sense to me. Can you provide some explanation? P.S. – Really appreciate your magazine!


Why is the Fuel Filter Filling Procedure Necessary on My 1994 C-1500 6.5?

Volume 2 Issue 3 - 6.2/6.5 Issues and Answers

I have a question for you about my 1994 C-1500 6.5. I have always wondered why my owner’s manual does not explain the fuel filter filling procedure that is necessary when the filter is changed. I am finding now that other 6.5’ers do not have to refill their filter housing after a filter change and I am curious as to why my truck requires this when others do not. Any thoughts?



maxxTORQUE in Print

(Available through

Follow us on Twitter