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setup for 26,000gcvw on a 6.5

iirc the 2500 with 6.0/4l85 keep then tcc engaged while decell till a certian speed... including the 6.6/4l85 in the vans iirc
the week link in the 4l80 is the 4th gear clutch pack followed by the direct clutch roller/sprag unit then TCC the clutch packs will slip before the hard parts do.

now i have been told that the input shaft is different between the 80 and 85 and few others parts that i cant excatly remeber right now.
 
seams ~200hp aint quite enough HP to pull 4th gear at 60mph with more then a 10mph head wind... :(

seams im going to be putting a Dmax in soon..


on the old ECT dmax clutch issue... i havent been able to get the ect past 205*
 
isspending 1500 between tune and att for maybe 75-100 hp increase worth it to ~5000 and better mpg with dmax swap really need 100-150 more reliable hp just to keep up with traffic
 
Might be easier and cheaper to take the radiator cap off and drive another truck under it. Engine swaps can get real $$$$$$ real fast. I really doubt you can do it for less than $20K unless someone gives you the engine and transmission. It adds up fast.
 
honestly,
low milage dmax is4-5k from junk yard
ppe stand alone 1000
harnes 200-300
tci controller 700.00
i got just about everything else.
stock lb7 power 300/520 would let me 4th gear...
the main problem is i cant run 4th gear more then 50% of the time.. thats 50mph @2500rpm with tcc in lock up vs 60mph @2000rpm in 4th..
 
Are you wanting to use the allison too or are you using the 4l80? 3rd gear in the 4l80 is the same as 4th on the allison.

Just trying to figure out what tranny you are talking about pulling in 4th.

The 4L80 wont like +300 HP on stock tranny parts. Their Overdrive is the weak link.

The allison can take a beating (ive done some beating on mine) but still does like extra power.
 
tanman_2006 said:
Are you wanting to use the allison too or are you using the 4l80? 3rd gear in the 4l80 is the same as 4th on the allison.

Just trying to figure out what tranny you are talking about pulling in 4th.

The 4L80 wont like +300 HP on stock tranny parts. Their Overdrive is the weak link.

The allison can take a beating (ive done some beating on mine) but still does like extra power.
Click to expand...

honestly your not telling me something i dont already know about the 4l80..
allison has some 200-250lb on the 4l80 allison as a .70 to 4l80 .75 od gear

cruising at 60-65mph(truck traffic speed) in 4th on the 4l80 is while being able to pull mild hills is what i want.

got to remember 300-400hp max output is not what your using when cruising down the road.. some people seam to forget that :mad2: ..
i would be very content if i could pull 5% grade at 55mph with full load that would be 3rd gear (80E) i can make a 4l80 live under 260000 with upgrades, be even easier with 4.63 gears in the back. take alot of the work out of the tranny and puts it into the differential..

BTW this is/was my dmax in sept 09 i broke stock tailshaft yoke with stock turbo and cp3 and no transfer case. running a SC4 1056 tranny
247' http://youtu.be/Ap-WErck4kE
268' http://youtu.be/B9uO9pL7-wo


with all that laid out there..
it seams with even a ATT tuning i would be lucky to see 10-12mpg vs dmax mild tune and i will see ~15mpg


gues i answered my question... unless someone knows something about getting 300hp out of a 6.5 and be relieable .... which i know very little about.
 
malibu795 said:
gues i answered my question... unless someone knows something about getting 300hp out of a 6.5 and be relieable .... which i know very little about.
Click to expand...

What about going after the gearing with a GearVendors and using the ‘underdrive’ when necessary? GV + turbo + ECM tune is less than the Dmax from a bone yard and the misc parts.

And for reliability, stud girdles?
 
JayTheCPA said:
What about going after the gearing with a GearVendors and using the ‘underdrive’ when necessary? GV + turbo + ECM tune is less than the Dmax from a bone yard and the misc parts.

And for reliability, stud girdles?
Click to expand...

current setup is 4.63:1 gears with 32" (225/70/19.5)
4th gear @ 60 mph is 2200
3rd gear @ 55 mph is 2700

IMO GV is pointless with out the power to pull in OD either via GV or the trannies OD gear.
 
You're just underpowered Adam, that's pretty obvious. Maybe there's a way to get the 6.5 up to snuff without going to the DMax swap though. Do you still have the OTR gig? Or is this gonna be it now...?
 
this it. signed the lease monday... getting me close to a lb7 power level 300/520 would make big difference... im pretty sure if i ran 4.10 gears i would be worse off..
second load i have hauled.. between the head wind and weight i had trouble maintaining 55-60 when i was headed home. 10,500lb worth of block for lowes.. got another load head to va/nc line by I95 for monday delivery 11,500 on that one... thats going to be fun....:rolleyes5:
 
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Its not so much if it can pull the load, but how about stopping it? 26K with the brakes of that time is a lot and if you get in a wreck and they find out your overloaded they my not pay.

Greg
 
I understand being short on power but it seems (from other peoples testimony) that the ATT makes it feel like you added more than just the 50HP because it flows better and improves MPG.

A duramax in that rig will be awesome no doubt, I still think the allison in that set up would be perfect. IIRC 3500hd's already have a body lift and should clear the tranny just fine. I agree you arent using full HP going up hills but I bet running 2200 RPM you would be using MOST of the torque (i mean thats what diesels are built for)

I cant weigh over 22,000 in my 93 3500 nv4500 (in my sig) without having to drive in 4th 1:1 gear. At 65 that shows 2400 rpm doesnt run hot but i am not sure what the EGT's are pulling like that. I get about 9-11 mpg loaded at 28,000 hauling hay for our farm.
 
Maybe a solution would be to slow down, run in OD empty and run in 3rd ( direct) loaded at 55 to 58 mph. When you get on long grades get in the right lane drop a gear and relax. A lot of trucks can't pull a 5% grade in OD or even direct at max GVW. Make some money the way you are set up now and in a year or two sell the old truck and get a little more truck the next time. Or just run the way you are and be satisfied. A one off truck might be fun, but could be a problem if it breaks a long way from home and you have to find a shop to fix it. I applaud your ambition on the Duramax swap, but those projects always take 4 times longer to do than you think and cost at least twice as much as you best guess.
 
I think he's got most of the parts he needs for the swap and I think hes got the Balls to get it done. Also IF he can keep the Dmax fairly unmolested for the swap parts should be easy to get, It is all GM parts. They also ran the 4l85 behind the dmax so those parts will match ok.

The only one off parts should be the mounts, Radiator, innercooler, ac condensor, oil coolers (gonna need to upgrade those weather you keep a 6.5 or put in a dmax), and wiring (unless you do a full interior swap). I think they used the same radiator in LB7 as a 6.5 for the 01-02 models so a 6.5 rad should work but hose routing might be an issue as well in IC piping and exhaust down pipe.

The reason for not getting a newer truck is because the 3500HD has a high gvwr, is light weight, and GM stopped making a regular truck version MD truck in 02(might be wrong) and went to heavy kodiac trucks. Power:Weight/tow capacity matters.

Have you talked to Fermanator about his swap? Might be a good idea.
 
Your issue with the 4l80 will be the converter. Each time my trans ate itself it was the converter that went. All the internals were fine.
 
LanduytG said:
Its not so much if it can pull the load, but how about stopping it? 26K with the brakes of that time is a lot and if you get in a wreck and they find out your overloaded they my not pay.

Greg
Click to expand...
I want to say the 3500HD he has runs 15in disc all around, much better than the 2500-3500 trucks of that era
 
LanduytG said:
Its not so much if it can pull the load, but how about stopping it? 26K with the brakes of that time is a lot and if you get in a wreck and they find out your overloaded they my not pay.

Greg
Click to expand...
see answer below.....
Joey D said:
I want to say the 3500HD he has runs 15in disc all around, much better than the 2500-3500 trucks of that era
Click to expand...
correct joey... iirc the only truck that currently come from the factory with 14" disc are 10? and 11 and newer the 01 newer run 13" disc everything else was disc13"/drum setup 13x2.5 or 13x3"

as for the trailer it has 8k axles and 215/75/17.5 wheels with 12x2 7/8"vs your common 7k ith 235/85/17 and 12x 2.25 brakes.
i am runs ~80% of axle capacity all the way around full axle cap is 32,000lb... handling wise you dont notice the wieght as in lane change stoping turning.. mirrors and accell and hills, and a smoother ride let you know its back there...

the ferm is out of this after i refused to accept his valued opinion as final say on running a dmax fan clutch from hayden and lb7 blade... which i have yet been able to get ect past 210*... havent even heard it rawr yet on this truck ....
i got loaded with plastic fence 11,500lb and is 7.5'x8.5' wide making my over all hieght just under 11' and i have a delivery in spotsilvaina(sp) VA (I95 by VA/NC state line).

as for the 4l80 build imo would be foolish not to upgrade the convertor that includes TCC upgrades as well either big single or tripple disc

as a professional semi driver and current Class A holder i know about speed.. ran out west in a truck that was governer to 65 were everyone else was runing 75-80... my biggest worries wasnt hills, or the 65mph sustained cross winds it was runing ~10-15mph slower then everyone else and is a risk for getting rear ended by a distracted driver... only good thing is there is 1/4 the traffic out there then in the midd west.. reguardless whos fault it is it will cost me money in down time and the customer for late produst. your current fleet 450hp semi at 80,000lb avg 60mph when gov at 65mph. that is all i am asking.

tanman yes then 3500HD was stoped in 02 both 01 and 02 cam with either 6.5td/4l80 or a 8.1/allison with still the same gear set of 4.63/5.13 options... those truck would be the best option for dmax swap... mainly the 8.1 due to is sares alot of the harnes stuff.. but your talking 13k truck instead of a 6k truck.

ideally the swap would include LBZ with 4088 or stock with towing tiwns stock cp3 and efilive... and a solid 400hp tune. bump the gear to 4.30 from the oem setup. that would setup would let me being able to run 5% grads in the low-mid 5Xmph and still hit 15mpg vs 9mpg i seam to be avg
 
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