I just recently bought my first ever Chevy 6.5 diesel. I have had about every other kind of diesel you could have but never a 6.5. Anyhow, this one I bought is a 98' that has only 54k miles, never pulled hard, never had a gooseneck or fifth wheel in it even. I did not need this truck but It was in good shape and the price was right so I bought it. This truck won't see too hard a use, mainly an ocassional pull up to about 13,000 lbs. First thing I am thinking about is the exhaust, looks extremely restrictive to me? Especially that little crossover pipe? I am not going to add any power, but I still think a better exhaust is neccessary. What are opinion on that? Also, the truck just had a new PMD installed and I was reading about these relocation kits for them, is that worth the money? The other thing I am considering is one of these bigger fan with different clutch kits for more cooling yet, what do you think about that? Anything else I should be looking at?

Luke,

I originally had a 94 GMC 6.5 all stock it was a great truck, But my dually is a completely different animal as you can see from the list of improvements a lot has been done to it. As far as the exhaust goes I can say that compared to stock there is a very noticeable difference. There are many PMD relocation kits for sale on e-bay all the time it’s a pretty simple straight foreword mod, I think it’s a good investment. Feel free to PM me if you have any other questions

ATS exhaust huh? They are pretty pricey aren't they? I saw Jerry Jardine's on Ebay for $275 plus shipping. Don't know if it is any good?

I can suggest:
New Downpipe(the stock one is quite restrictive)
Larger exhaust(4 inch?)
Crossover(are the aftermarkets larger?)
Gauges(EGT, Boost, and Tranny Temp if your going to pull)
Relocate the PMD(You can make your own kit if you don't want to shell out the cash)

Good luck with your new 6.5!

$275 doesn't sound to bad mine was already installed when I bought the truck. I remember when I had My 94 back in 96 they where going for 4 to $500

Primer is definitely rite if I didn’t have my turbo temp gauge when I pulled my fifth wheel the first time I have no doubt that I would have toasted my turbo.

Ok, just was out looking over this truck. It has four other coolers in front of the radiator. I know one of them is the A/C condensor, but what are the other three? The great big one right in front of the radiator I presume is the A/C, then there are two smallers ones in front of that side by side that are the same size, then there is a real small one all the way to the drives side next to the other two in the front.

The two in front the same size are your tranny cooler and oil cooler the smallest is for your power steering and your rite about the two big ones

So it has a tranny cooler on it all ready. What are the two metal lines running in to the passenger side of the radiator? Are those also transmission related? I don't know, this truck all ready has had the muffler removed before I got it and somebody put a crappy dual tailpipe system with like 2.5" pipe from about where the factory muffler was back. I think I am going to rip that off of there, and step it up to a 3.5" or so pipe as far forward as I can and run it back to about two feet or so behind the cab and dump it out with a turndown in front of the rear axle simaler to the new style cab & chassis. How does this sound? I don't hardly want to spend the dough for a complete system as this truck will not get pulled too hard, as I still have all my Dodge's to pull with. I am thinking, redo the exhaust as I have stated above, relocate the PMD, and maybe do the fan swap that I saw on John Kennedy's website? Also, possibly thinking about a mag-hytec style trans pan, as I all ready have a lot of trans coolers on the truck it seems?

This truck won't see too hard a use, mainly an ocassional pull up to about 13,000 lbs.
Uh, 13,000 lbs. is a lot for a 6.5, especially if you're going to be towing it up any kind of grade. If you bought it for that kind of use, I think you bought the wrong truck, or at least the wrong engine.

Well, I hope not. I am used to Dodge/Cummins and for them 13,000 lbs is a light load. My Dodge's pull upwards of 30 sometimes, and on a rare occassion, a little more. The trailer this truck will pull is a 24' gooseneck stock trailer that weighs 6,000lbs. with maybe two or three horses or cows, for a total of around 8k-10k. Also I will load this trailer with 140 50lb. square bales of hay(7,000lbs) for a total of 13k. It'll have to pull a load like that maybe 10-15 times a year. Maybe I am naive but I thought this truck would handle that kind of load? Will it or won't it? If not, I need to do something different???:help:

Stingray, I see in your sig you have the Jardine exhaust? What do you think of it? I was thinking about them or maybe one from SSdiesel supply.

Stingray, I see in your sig you have the Jardine exhaust? What do you think of it? I was thinking about them or maybe one from SSdiesel supply.
Very pleased with it. Fits great, quality components, good price. It's a little loud, but I can always put a quieter muffler on if I choose to.

What about the stock cross over pipe, is it sufficient? Or must it be upgraded too?

Am I really going to melt this thing pulling 13k once a month? I really thought this truck would do it? It does have 4.10 gears.

I'm running a Jardine as well. Installation was incredibly easy.

There is a near bolt-on relpacement AT cooler that is about $70 and made by the OE mfg with much greater capacity. I think TurbineDoc is running it.

With a dually and 4.10's I'd go for it no hesistation. Take it easy, get gauges and drive by them. Check out the diagnostics at the beginning of the 6.5 forum and make sure your lift pump, turbo, wastegate, clutch fan, etc... are all functioning properly.

Oh, and don't drive it like a Cummins...):h

Chaser

Stingray, I see in your sig you have the Jardine exhaust? What do you think of it? I was thinking about them or maybe one from SSdiesel supply.

Man, I am starting to get nervous here. I may have really screwed this up, as I just read the owners manual and it shows a max trailer weight for this truck of 7,500lbs! That'll barely cover my dang trailer, and that is my lightest trailer, I have heavier. What have I done here?:confused: -:t

What about the stock cross over pipe, is it sufficient? Or must it be upgraded too?

Am I really going to melt this thing pulling 13k once a month? I really thought this truck would do it? It does have 4.10 gears.

The crossover pipe is sufficient in stock form. The aftermarket ones aren't any larger, just mandrel bent. Only reason I replaced mine was because the original was rusted out and leaking. The downpipe is restrictive in some trucks, as it was bent by bubba - no mandrel bends in that thing - kink and dent city.

You can pull 13k lbs. with it, but don't expect to do it quickly up hills if you want your engine to last long. Pulling 13k up a steep grade, going full throttle the entire time will kill it prematurely. It'll last for a while like that, but don't expect 200k. Cracked blocks, cracked heads, and occassionally cracked pistons are common side effects of abusing it like that. It'll crack even faster if you crank the boost up and ignore the EGT's.

If you upgrade the exhaust, make sure the cooling system is good, get a boost, EGT, and tranny temp gauge set, and never let the EGT's get above 1,200 and the coolant temps above 230, it should last a while towing 13k lbs. Just don't expect to maintain 65MPH going up steep grades. It's only 195hp, and it's not a Cummins or a Dmax.

Man, I am starting to get nervous here. I may have really screwed this up, as I just read the owners manual and it shows a max trailer weight for this truck of 7,500lbs! That'll barely cover my dang trailer, and that is my lightest trailer, I have heavier. What have I done here?:confused: -:t
That doesn't sound right for a 3500 dually. My 2500 Suburban is rated at 6,800 lbs. towing capacity, so a 3500 dually has to be a lot more than that.

From everything I read here the stock crossover isn't critical like post-turbo breathing and losing the soot-trap if you can.

I elected to leave mine alone since it is in good shape and I could find no quantified benefit of replacing it like can be found for the turbo-back exhaust systems.

Chaser

What about the stock cross over pipe, is it sufficient? Or must it be upgraded too?

Am I really going to melt this thing pulling 13k once a month? I really thought this truck would do it? It does have 4.10 gears.

I'd look in the door pillar for GCVWR. Even so they are generally pretty conservative IMHO. (You're Cummins likely aren't rated for 30k for example.)

My old 1983 LandCruiser had a 3500 lb tow rating and pulled 6k regularly - albeit quite slowly up grades. Braking, I beleive, is a big factor in the ratings...many vehicles will pull more than they can stop...my LC was a good example of that, too!:eek:! .

Chaser

Man, I am starting to get nervous here. I may have really screwed this up, as I just read the owners manual and it shows a max trailer weight for this truck of 7,500lbs! That'll barely cover my dang trailer, and that is my lightest trailer, I have heavier. What have I done here?:confused: -:t

Here's a list that'll really mess with ya'. And I bet it's compiled from factory data. http://www.trailerlife.com/towratings/tr99_chevrolet.cfm

Shows a K1500 5.3 w/ 4.10's at 8000 lbs...500lbs stronger than a K3500 6.5 w/ 4.10's at 7500 lbs.

And it shows a C1500 sub w/ 3.42's at 8000 lbs, but a C2500 sub with 3.73's or 4.10's is also at 8000 lbs. No benefit for gears...

Geeze!?!

Chaser

So it has a tranny cooler on it all ready. What are the two metal lines running in to the passenger side of the radiator? Are those also transmission related? I don't know, this truck all ready has had the muffler removed before I got it and somebody put a crappy dual tailpipe system with like 2.5" pipe from about where the factory muffler was back. I think I am going to rip that off of there, and step it up to a 3.5" or so pipe as far forward as I can and run it back to about two feet or so behind the cab and dump it out with a turndown in front of the rear axle simaler to the new style cab & chassis. How does this sound? I don't hardly want to spend the dough for a complete system as this truck will not get pulled too hard, as I still have all my Dodge's to pull with. I am thinking, redo the exhaust as I have stated above, relocate the PMD, and maybe do the fan swap that I saw on John Kennedy's website? Also, possibly thinking about a mag-hytec style trans pan, as I all ready have a lot of trans coolers on the truck it seems?

On the Fan. My 98 had a steel 9 blade fan. The Duramax fan is a 9 blade metal. You might be OK with just the new fan clutch. Mine was locked up solid. I got the 9 blade plastic before I knew I had a 9 blade. Older ones had 5 blade fans from what I've read. The clutch just kicks on earlier. Keeps max temp down.

On the Fan. My 98 had a steel 9 blade fan. The Duramax fan is a 9 blade metal. You might be OK with just the new fan clutch. Mine was locked up solid. I got the 9 blade plastic before I knew I had a 9 blade. Older ones had 5 blade fans from what I've read. The clutch just kicks on earlier. Keeps max temp down.


Interesting, I better go out and count.

Interesting, I better go out and count.

Ooops... I meant... DuraMax upgrade fan is 9 blade plastic. My 98 is a 9 blade metal.

Don't know what extra I will get from the 9 Blade plastic. But I already bought it so, I'm slapping it on.

The Upgrade fan clutch kicks on earlier then the standard clutch. Nice addition.

iirc the Duramax fan is wider? Like these guys are telling you Luke. Exhaust comes first and then follow with the rest.

I am fairly new to the diesel scene, but there are guys on here that regularly tow with their 6.5. The most common problem is high egt when pulling a hevy load up a grade. If it were me I would open up the exhaust 3.5 inch is plenty,get a set of gauges (pyro,boost and trans temp), and put on an ic. As I said I'm no expert but from reading this forum I believe these will be beneficial upgrades.

Well, I may regret it but I guess I'm gonna give this thing a try. Didn't think I'd have to spend this much money on this truck to pull a measly 13,000lbs:(

Here is a list of what I am going to do..............

-3.5" or 4" exhaust
-PMD relocation/cooler
-fan and fan clutch upgrade
-EGT gauge
-deeper trans pan with trans temp gauge.

Dang it, there is well over $1,000 worth of stuff and I still may melt this sucker. My wife is not going to be pleased, as she is a Dodge lover anyhow, and she pulls that much weight with her bone stock Dodge 3/4 ton 12-valve automatic with 3.54 gears. I tell ya, if I spend all this money on this thing and still crack a head or block I am gonna be hot:mad:

Do what you're comfortable with, but...

If your PMD is still in the land of the living...you might hold onto that $$ for now. I'm running mine on the IP till it dies and will spend the cash when I have to - which I'm 11,000 miles logged already on a PMD the prior owner installed. I'm sourcing a 'glovebox' PMD to get me home (should I need it) in the meantime - meaning a good used unit.

With a Jardine exhaust, egt and tranny gauges - and a bigger tranny cooler (which will increase fluid capacity and cooling - not just fluid capacity) you should be in good shape.

The '98 already had the HO water pump and dual thermostat housing and 9 blade fan, so you're cooling is going to be better than many already.

I'd wait on the PMD and cooling upgrades, get the others done, hook up your trailer and watch the gauges.

You could reflash the ECM for the money saved and *really* help out the pulling/shifting/and possibly EGT's under load... JMHO...

Chaser

PS - I'm still amazed that be it a Dodge, Ford or GM, the highest tow rating for all of them is still a big fat gasser...:mad:

Well, I may regret it but I guess I'm gonna give this thing a try. Didn't think I'd have to spend this much money on this truck to pull a measly 13,000lbs:(

Here is a list of what I am going to do..............

-3.5" or 4" exhaust
-PMD relocation/cooler
-fan and fan clutch upgrade
-EGT gauge
-deeper trans pan with trans temp gauge.

Dang it, there is well over $1,000 worth of stuff and I still may melt this sucker. My wife is not going to be pleased, as she is a Dodge lover anyhow, and she pulls that much weight with her bone stock Dodge 3/4 ton 12-valve automatic with 3.54 gears. I tell ya, if I spend all this money on this thing and still crack a head or block I am gonna be hot:mad:

I have been reading here, and with my truck i recently towed 11k to seattle and back home this is a yearly trip for me but this year i had the upgrades of a intercooler and a boost controler and a boost fooler, let me tell you it was a huge differance i held 60 up vantage hill both ways by the top my pyro hit about 1150, but thats alot better than last year when they 1300 towards the bottom so i had to let out of it and crawl about 40-45mph up the hill, so i guess i am saying these engines do good just not it stock form be prepared to spend a little money and they should do just fine

Wagonwheeler, my PMD is new, this truck was in my shop having that done the week before I bought it from the previous owner. The cooling seems good on this truck, even though I haven't hooked anything to it yet, with outside temps in the 80's the temp never gets over 180 on the gauge, we'll see how it acts with a load? Maybe just an exhaust, EGT/tranny gauge's, wil get me by for now, we are coming into fall and winter after all, and most all of our hay is sold and delivered, so we'll not be hauling any heavy loads in hot temps untill next may or june, unless I get warm enough temps in the next two weeks to get my third cutting off, then I'll have another 2,000 bales to deliver yet this fall. It's getting a B&W gooseneck hitch in it this week, so maybe this weekend I can hook something to it and see how it acts.

Hey 1994sploder, I see in your sig, you used a 3" downpipe to a 4" exhaust dumped ahead of the rear axle. I was thinking about something like that to save money. Will a straight 3" piece of straight pipe hook up to a 3" downpipe and make it past the two frame crossmembers without rubbing them? Or do you need a specially bent piece to clear? I was thinking straight 3" past those crossmember, I could step up then to a 4" new Dodge take off muffler I have laying here, and then a turndown? How does this sound for a cheap exhaust, would it be all right? I have all the pipe and muffler at my disposal, all I'd need is the downpipe.

Luke,
I did my exhaust a couple of week ago, and on my `96 there was plenty
of room over the k-members for a 4" straight from the the 3" downpipe.
I think the earlier yr trucks have a different trans k-member.

Your Idea for a cheap($) system sounds good,If that muffler flow well enough.

SSDiesel has the 3" to 4" downpipes.

Luke,
I did my exhaust a couple of week ago, and on my `96 there was plenty
of room over the k-members for a 4" straight from the the 3" downpipe.
I think the earlier yr trucks have a different trans k-member.

Your Idea for a cheap($) system sounds good,If that muffler flow well enough.

SSDiesel has the 3" to 4" downpipes.


I just wasn't sure if a straight pipe would go through the crossmembers. My truck still has the cat which is going to get lost when I do this. I guess I'll just try it and see? I was going to get the 3" dp from SSDiesel, then go from there with the stuff I have. The 4" Dodge muffler should be more than good for a stock 6.5? After all it is good enough to flow 325hp/610ft-lbs from a Cummins with no problems, I'd think it'd work.

warpspeed has a pretty good system $318.00 delivered, 3"down pipe 4"back with choice of mufflers or not

Hey Luke i got my downpipe from gorlicks exhaust it is longer than stock by about 18" it cost $33, as for the 4" pipe it fits but it is tight on my truck but no rattles it sounds good it is loud inside the cab only on a hard take off but at cruise even with a load it is real mellow the 90 degree turndown helped alot all and all the whole exhaust cost less the $100 and i am happy with it, the reason i chose this style is one of my instructors in college told me that diesels like to exhale as much as possible as quick as possible and it works well

Alec

Hey Luke i got my downpipe from gorlicks exhaust it is longer than stock by about 18" it cost $33, as for the 4" pipe it fits but it is tight on my truck but no rattles it sounds good it is loud inside the cab only on a hard take off but at cruise even with a load it is real mellow the 90 degree turndown helped alot all and all the whole exhaust cost less the $100 and i am happy with it, the reason i chose this style is one of my instructors in college told me that diesels like to exhale as much as possible as quick as possible and it works well

Alec


That is why I was thinking of maybe running 3" or 3.5" past the cross members and then going to 4", I don't want any pipes rubbing the frame anywhere.

Luke,

If you are a hay farmer, you will need to frequently clean out the area between the AC condensor and the radiator. It's easy to do, and helps dramatically.

Luke,

If you are a hay farmer, you will need to frequently clean out the area between the AC condensor and the radiator. It's easy to do, and helps dramatically.

I don't use these trucks in the field. We use tractors and wagons. I use one of my Dodges to bring in round bales with my 48' trailer, but I haven't yet had any problems with it getting plugged up.

That is why I was thinking of maybe running 3" or 3.5" past the cross members and then going to 4", I don't want any pipes rubbing the frame anywhere.


Big help or not...... I used the Jardine exhaust on my 96 xcab dually. A little tricky to line up properly but good components and the the price is respectable. I called the number listed in the ebay ad and direct ordered.
The PMD (in stock form) is a real PITA to change. Wait til it breaks.

The 7500 lb. tow rating is for bumper pull.... I have used mine to move a 23' triple axle tilt deck (pintle and class v hitch) with a case 580 on top, or my ASV rc-50, or in a pinch a couple times put the cat 416 on it.

13000 with a g/n, I wouldn't sweat it. :ro)

I've got a quiestion about the exhaust myself. If the outlet on the downpipe is 3'' then would it really help having a 4'' exhaust pipe or not just wondering. I have 3'' straight pipe wright now but didn't know if four inch would do anything???

I've got a quiestion about the exhaust myself. If the outlet on the downpipe is 3'' then would it really help having a 4'' exhaust pipe or not just wondering. I have 3'' straight pipe wright now but didn't know if four inch would do anything???

Every time you bend a pipe, you add some restriction. That's why they go to a 3 1/2" or 4 " exhaust, even though we have only a 3 inch downpipe.

Well, I just got off the phone with Jardine's. I bought the 3" to 4" downpipe, and the intermediate pipe that goes over the crossmembers for $70 a piece and a muffler for $45. So I am gonna put all that together and dump it out about two feet ahead of the rear axle with a turndown and go. I know it is not a perfect system, but that is basically how Chevy builds the exhaust on the new cab & chassis, it's just dumped out right in front of the rear axle. So I am gonna try it. Should flow real good and I'll only have $185 plus shipping invested in it. My wife accusses me of being a German Jew, myabe she is right?

Also, I just ordered the trans trans temp gauge kit from SSDiesel. I am gonna hook it in the pressure test port on the side of the trans and see what kind of temps it runs before I blow a bunch of money on more coolers. Anybody got a picture of where exactly that test port is at?

You don't need a picture.....it is right above the shift linkage....easy to spot...