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setup for 26,000gcvw on a 6.5

So do you have a tune? Stock tune is too weak it isn't going to work for you. I won't get on the interstate with my 7K axled gooseneck loaded with much. (I have the stock tune). Around here the rolling hills (short but some steep kill me and speed yo-yo's bad). I agree it is stressful when you feel you can't accelerate and speed yo-yo's real bad.

Not that a tune will make it a Duramax but it will make it better in the mean time I am sure. Probably could sell the tune when you swap so it won't be a total waste if swap.
 
malibu795 said:
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
Click to expand...

I ran a precision billit converter tripple disc with no luck. Who do you have in mind to buy one from? Suncoast was doing them but i don't see them on the site anymore.
 
GM Guy said:
I give the ATT a try before giving up on the 6.5L, dont have one, but want one! :)
Click to expand...

Even with the ATT or any other upgraded turbo you still need more fuel which the electronic 6.5 pumps don't seem to want to produce
 
The ATT will get you in the ballpark. I doubt you will get 15 MPG from a Duramax combo because we did not with a 28' cargo trailer hauling 150 tires, parts, an engine, transmission, batteries, etc. Imagine a full height cargo trailer loaded to the ceiling with boxes on top of tires etc. In mountainous terrain of 7% grades we were doing about 9.5 MPG +- 1MPG. However we were at the speed limit easily most of the time. The oil temps were extreme enough to trigger the low oil stop engine warning at 9psi during a park to drive shift. This is with an additional cooler in 115 degree weather.

You should try synthetic and sample it. It doesn't matter what you run. Synthetic has a higher operating temp range before it fails. You will only know that your oil failed when you scuff a piston... At that oil failure point - it mattered. 2500 Mile oil changes on the 1993 with 6 quarts - what does your manual call for?

The 1993 taking the trailer got 7.5MPG at 43MPH because GM's turbo simply chokes over 2200 RPM when you need the power to maintain low climbing speed. The ATT allowed the engine to make power over 2200 RPM. I posted the results in the link below.

Forget where I posted it, but a steady climb from 1000' to 2000' from the landfill was part of the route. The light would usually stop me and traffic, good ole EPA planning -NOT! I would be happy to get to 65 MPH again before the 2000' elevation mark with the 1993/28' trailer/GM3 and foot on the floor the entire way. After building the Suburban with a 6.2 and an ATT I pulled the trailer from the dump and that same dumb light. It hit 70 before I lifted the throttle in short order and would go from 65 to 70 whenever I wanted to. I did not have to keep the ATT equipped Suburban floored.

The engines displace nearly the same. The IDI and 2 valve design hold you back some. So does the weak crack prone block. However there is a lot of power left on the table in the upper RPM with the GMx turbo. 12 quarts of oil that go 10K on a Dmax vs 2500 miles for 6 quarts in a 6.5 is cost savings. One injector set and the 6.5 just won...

http://www.thetruckstop.us/forum/showthread.php?32683-Payson-AZ-Turbo-pull-off-*Round-1*

As far as transmissions: The 4L80E is weak in the compression braking department. The overrun clutches will slip and burn up first if used hard esp with a TCC override switch. I got 50K out of a fresh rebuild before the TCC clutch was gone and most of the miles manual 2nd compression braking had burnt up completely. So I would say be easy on the trans for compression braking.
 
ww i can see your point out in your area. i am mainly running east of I29 midwest, new england, and south... there is alot more flat land there... there is hardly any 6% grades and a several handful of 5% grades out here..
i know several people that hotshot in the 15mpg range...both dodge and GM...
i am currently avg ~9mpg.. 2700rpm seams to be the choke point on this setup..

oil temp i stuck a OT guage in then supply side cooler line, i have seen up to 180* temp pre cooler usually is 125-150* while pulling city driving its can get hot (180*)... it started leaking so i have swaped in PMDcable line upgrades... napa sels a 7qt pan that i plan on picking up and weling a 1/8 npt bung into the side to get temps there.. might even weld some fins on it to aid in cooling
oil service interval... IDK never got a manual with the truck.
tax return is coming in soon.. probly pick up a heath tune and maybe the ATT at the same time...

on your rebuild, did you run stock brown clutches and steels or upgrade to red clutches and kolene steels?
fwiw 600.00 i can swap out clutch packs and 2nd man band and software in the tranny.
joey
i have talk with hughes, TCI, and PATC about convertors i would be geting one built to handle more then what i plan on running through it. both the th400 and 4l80 have problem with the stator suport bushing goign out and allow exsesive play on the front of the tranny
 
malibu795 said:
joey
i have talk with hughes, TCI, and PATC about convertors i would be geting one built to handle more then what i plan on running through it. both the th400 and 4l80 have problem with the stator suport bushing goign out and allow exsesive play on the front of the tranny
Click to expand...

Would this cause the converter to self destruct?
 
if there is sufficent play on the stator support you could actually bolt up the TC off axial and make everything out of ballance
34016-W.jpeg
 
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well update. i guess.. to a load ao the snap together white fence to southern VA sonday 11,500 worth.. 5% grades run about 33mph still running stock engine fueling setup no turbo master
the more i pull(miles) the better it seams to get:???: there is gray gm form a gasket on the valve covers and oil pan....
couple pic that i remeber to take
10,500lb of stone on 3 pallets

this was 8,500 might as well been 12 tons for the air it caught going down from cincinatti to louisville... i think i broke even on that one..:mad2: ect was 205-210 for about 80 miles from the hills and air drag.
[URL="http://sphotos.xx.fbcdn.net/hphotos-ash3/531039_3378971506644_1040072946_3140346_1547817192_n.jpg"]

i can maintian 60-65 decently. proble get heath tune once i get more into the flow of things
 
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malibu795 said:
true... im more worried about tranny temps right now
http://www.summitracing.com/parts/DER-14207/
the plan is this.. adds a 1qt or so plus have built in 1/8npt bung for temp unit..
Click to expand...

I just pulled around 7,000+ LBS trailer from Killeen, TX to Denton, TX. My transmission temp gauge on my NV4500 slowly crept up to 250F. It maxed out the gauge so, I have no clue how hot the trans got. It took over an hour of non stop driving to get it up to 200F. It then reached 250F about 45 Minutes later. About 2 1/2 hours into my trip the gauge was maxed. I even took the trip slow and drove up there at around 60mph. I know the fluid level was good. It had new clean fluid in it also.

I wonder if this is normal?

I did make a pit stop in Plano, TX for a few hours. When I finished the trip to Denton, TX it never got above 185F. That trip was less than an hour drive. It also rained the first half of the trip.

The rear end with the new mag-hytec never saw above 185F.

The trip home neither one went above 185F. But, the trailer was empty.
 
What gear lube do you have in it? The purple GM stuff or Mopar stuff is the only way to go in the NV4500. There are some add-on coolers that replace the PTO plates. They add capacity and are finned to improve cooling. Seems like I remember that most folks overfill by a quart or so through the shift tower- helps with 5th gear.
 
the problem with the nv4500 is outside the airflow under the truck there is no other means of cooling the fluid...
in all honestly ~14,000lb should not heat up a nv4500 like that.. except for one reason.. hauling something that created alot of wind resistance.
 
skypilotj said:
anyone got part numbers for the 9 blade mod and fan clutch?
Click to expand...

i pulled the blade of my 02 that doesnt have an engine or tranny currently.. the clutch i used is hayden 2886
these are also hayden spin on fan clutches. 2840 <- 6.5 2843 and 2850 dmax.
ferm ademently mention that one can over heat the 6.5 with the dmax clutch on the std C/K body style, in page 2 and 3 of this thread.
 
malibu795 said:
the problem with the nv4500 is outside the airflow under the truck there is no other means of cooling the fluid...
in all honestly ~14,000lb should not heat up a nv4500 like that.. except for one reason.. hauling something that created alot of wind resistance.
Click to expand...

I was hauling a flat bed trailer with a 1992 Chevrolet K2500 reg cab long bed truck.

Maybe I am wrong but that load should not have caused too much wind resistance.
 
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