• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

setup for 26,000gcvw on a 6.5

malibu795

malibu795

misspleelleer..........
Messages
961
Reaction score
0
Location
south charleston ohio
i have this
99 3500 HD (86000 miles) getting my ducks in a row for a run hotshot
what needs to be done to handle that weight?
been told
water pump up grade
injectors are a life aroun 80-90k
pmd relocation
ecm tunning
waste gate mod
exhaust 4"

any more info would be helpful
 
Last edited by a moderator:
Truck looks great!:thumbsup:
I don't have a specific answer to your question Adam and I KNOW there are plenty of guys here that have them but I wanted to chime in and say HEY! Good to see you back around...:D
 
malibu795 said:
i have this
99 3500 HD (86000 miles) getting my ducks in a row for a run hotshot
what needs to be done to handle that weight?
been told
water pump up grade
injectors are a life aroun 80-90k
pmd relocation
ecm tunning
waste gate mod
exhaust 4"

any more info would be helpful
http://a6.sphotos.ak.fbcdn.net/hpho...8077284464_1040072946_3014159_384719516_n.jpg
Click to expand...

That's ALOT of weight for a 6.5 to handle. Check and see if you have the bolt on or spin on fan clutch. If it is a bolt on style then you have the 1st design HO pump, if it has a spin on it is the 2nd design with balanced flow that is prefferred. If it is a bolt on I would change it out for a spin on and a new fan clutch. Also you may want to consider a DURAMAX fan blade as it moves ALOT of air(don't know how it compares to the late model 20" steel one though). A 4 exhaust with 3" down pipe should be mandatory, relocated FSD outside the engine bay on a heat sink, and a tune would also be a good idea. For that much weight, you may also want to consider swapping out the turbo for an ATT to help manage EGT's with the weight. And even though you only have 86K miles, I would still do the injectors as well.
 
I have grossed t 22,000 a few times with my truck and the mods were minimal.

You should really consider upgrading to a larger more efficient turbo and obviously an upgraded exhaust and tuned ecm
 
I grossed 36,000 in my avatar and only squatted the truck 2in. The springs can handle it. The turbo is a must and gauges too. I use mine for hot shot work too. My clutch doesn't like the loads so I chewed up my synchros and smoked the clutch, looking into a custom clutch and possibly 4.56's.

What length is your bed? I would kill for a 10th foot bed 3500hd.
 
I would do a whole cooling system refresh. clean the rad, new thermostats, fan upgrade, wp, etc.... Bigger turbo would help you a lot and a walbro lp would be a good addition to keep the fuel flowing when your really getting on it.
 
I would get the ATT and a tow tune.

I've towed in excess of that without problems.
 
I would go and get an additional bank loan if you have to for an ATT, 4" exhaust, tune, and refreshed injectors. You want to avoid China nozzles at all costs! look up posts on injectors on here...

Your 1999 cooling system should be good as is: as long as the radiators are clean and the fan clutch is less than 5 years old. I think the HD's have a bigger radiator. If you don't know the fan clutch age REPLACE IT as they loose 200 RPM per year! I have already ruined one 6.5 over a bad fan clutch. DD can get away with old fan clutches that sort of work: Hotshotters can't.

If emissions and the kitty matter get a 2008+ 4" duramax converter or the aftermarket 4" spun metal high flow unit. I do not know if the HD's have kitty problems to deal with, but, in case they do...

The GMx turbo you have when pushed hard will turn ~3 MPG into engine heat and you will listen to your fan scream on any hill. That and lack of power over 2200 RPM will drive you nuts. I went from 7MPG to 10.4 MPG by changing the turbo to ATT and top speed of 43 MPH (GMx) to 55 MPH (ATT) on 7% grades. HD's MPG will vary from my results I am sure...

Turbo Masters give you more power, but the ATT gives you more. The TM's do not affect MPG under higher loads. Light loads they can hurt MPG's.

Your biggest expense will be fuel. So monitor your MPG and then you will get your cost per mile and cost per day. The fuel economy improvement with the ATT will pay for itself quickly and you get to write the cost off on taxes.

Did I mention you need better turbo yet? :wink5:

If funds allow you should also add a turbo blanket and header wrap the down pipe 1' past front bend in the floor pan and the crossover.

I wouldn't tow or haul more then the truck is rated for. I don't know what the HD's can handle, but, you should if asked by the DOT...
 
IIRC, the HDs only got a bigger radiator on the gassers. the diesels are the same size, but IMHO cool slightly better, due to the lower part receiving more air than what the nostrils provide.

the HDs are rated for 15K GVWR. I will look up the GCWR for you if you would like, but it will be low. GM either used the 6.5L or the transmissions as the limiting factor. IMHO, the HD chassis is good for quite a bit more with the 4 wheel discs and the big frame.

what transmission do you have? both might require better cooling for long distance tows. they make some cool PTO finned covers for the 5 speed.

what trailer will you pull? gonna put a bed on, or just flaps, lights, and quarter fenders? is that the 159.5 inch wheelbase that takes the 11 foot bed?

one thing to watch out for is that rear end. in the owners manual, it will tell you that severe use (towing, running over 45 mph, running near max GVWR, etc) to change the conventional gear oil ever 3K miles. synthetic oil? every 30K miles. The reason is due to some desgn flaw in the axle that puts alot of stress on the ring gear carrier bearings or something like that. I would say some amsoil from a vendor and a mag-hytec diff cover would go a long ways towards sucess.

If I interpret the law correctly, it isnt what you weigh, but what you could weigh that matters to the DOT, so if I was you, I would find a trailer with dual 5200 lbs axles (or if you are friendly with a trailer mfg, get them to stamp it for 5200 axles, and run 7K axles for bigger bearings) I did spec out but never ordered a Kaufman 25 foot bumper pull with 5200lb axles, and it was pretty affordable. otherwise, any bigger than 5200lb, you are over 26K GCWR.

otherwise, do as the others suggested, if it isnt spin on, upgrade it, make sure the rad is clean and fan engages, etc.

good luck!
 
trailer will be a 26+4` deck over kauffmen with 8k axles and 17.5 tires it weighs ~4500lb plus the 6400 of the truck puts me 10900 empty and just under 15k payload capcity.
i am a cdl holder and driver for a living. DOT only cares what the rolling wieght of the vehilce is not what its rated for.. i can hot shot a class 8 semi truck if i wanted to but limit then gvw to 26k would be less then 8k of payload, and just need air brakes endorsment, not saying you wouldnt get harassed by the dot tho.. its perfectly with in then regs (which i have a copy of
truck weighs 6400lb 3800/2600 split.
rear axle is a D80 with 4.63 gears and 14" rotors and 10,000 worth of springs on it. the axle itself is rated for 11,000lb im going to through a magtec on there and forget about it.
yes wheel fenders with lights and lay some alluminum plate down the frame to clean it up.
4l80 is the tranny deffinently puttign a nice perma cool cooler on it.
looks liike the 155" wb little shorter then my 02cclb which is 178"
got a link for said ATT turbo?
walbhoro pump? like hte gasser inline one? or would something like airdog/fass or similar be just as good? what is supply pressure safe limit?
i got my dmax fan and clutch from my 02 laying around.
got to go.. leaving for washington state in a semi..
 
malibu795 said:
btw checked fan before i left. spin on hub and i have a dmax fan and clutch at home to swap in. one problem down
Click to expand...

DO NOT, I repeat DO NOT run the DMAX fan clutch. The DMAX 21" fan blade from 01-05 is teh prefferred blade, but the DMAX fan clutch is a HIGHER temp fan clutch than a 6.5's. Run a severe duty 6.5 fan clutch with the DMAX fan and you will be good, but the DMAX fan clutch will not kick in until close to 225 degrees whereas a 6.5's kicks in at roughly 210. It will spin right on, but I would NOT use it. As for your trans, install a LARGE trans cooler like the Earls Plumbing 42510AERL. It comes with AN fittings for it, but I'm sure you can find some adapters to hook it up to your lines. Also put a TRANSGO HD2 shift kit in it to help prevent pressure spikes and broken clutch drums in the trans. If you get a programmed ECM, make sure they know if you put a shift kit in it as they will want to leave the trans pressures alone in the tuning if so.
 
with the bigger fan and stronger clutch, is 15* that big of a diference?
beast mod? im not looking to turn the fuel setting up. just make what's there more useable and reliable. if things go well i will have a dmax in it next summer
 
Look up the feed the beast mod, it allows more fuel to the IP by increasing the size of the fuel line. It won't use more fuel, but it is there if you need it.

And yes 15* will make all the difference, these engines can crack the heads or block at 215-220*
 
thinking out loud here.
for every revolution the dmax fan pulls substantially more air through the radiator which doesn't have to deal with heat soaking from a cac on the dmax trucks.
Hayden has three part numbers 2840 6.5 2843 and 2850 are both dmax clutches. i will call them Monday to find out more on them
 
DO NOT RUN THE DMAX FAN CLUTCH! That's as simple as I can make it. If you do I believe you will be doing your swap ALOT sooner than later. The DAX fan clutch comes on at a hotter temp, and this includes the heated air from an intercooler up there. A 6.5 will NOT be happy because chnaces are the fan clutch won't kick in until around 240 or so which is WAY past the redline for a 6.5.
 
You must log in or register to reply here.
Back
Top