What do I need to do on a rebuild to get a 6.5L to live at full throttle towing?

[WarWagon]

As you can see in another post my 6.5L is as well oiled on the OUTSIDE as it is on the inside at the moment. :blindfold:

What do I have to do with the rebuild for heavy duty use? Where do I get parts like ARP head studs and new pistons?

I already have the temperature under control with mods as it does not go over 210.

It may have been just an injector failure and this thread is not necessary? I have 2 injectors out and I am pulling the rest now.

Max boost is in 4th, OD at 13-14 PSI below 2500 RPM.

Pyrometer was scheduled to be installed this weekend with a new LH exhaust manifold. Except the engine went first…

The route I have towing has a lot of hills. Basically I put it on the floor and leave it there for an hour. Speed changes to as low as 43 MPH. (Phoenix to Payson.)

A Cummings swap will not do me much good. The late model Dodge… It will keep speed, but, if you slow down it will not speed back up. The other Dodge committed suicide and popped a $1000.00 computer that got me this route as the Dodge owner did not fix his truck.

So do I put in 18:1 pistons?

Do I rebuild it stock compression? (And hope the new ceramic coatings prevent this issue again?)

Do I get a 6.2 military take out, lower the boost and use it?

The ATT turbo looks like a good choice, but, I have a hard time justifying the additional cost on top of a rebuild with a working GM3 and the value of this truck.

What do you recommend for this type of use? Is this a bad engine choice for what I need – wrong tool for the job?

 

[Matt Bachand]

I think this is what the ATT was made for. It provides EFFICIENCY, along with less heat. Keeps IAT's down, which keep everything down, and its alot less engine parasitic, especially compared to the older GM series of turbos. I think it's what the doctor ordered.

So not only does it take less engine to make more, but its gonna run way cooler.

HD work like that sounds like youd benefit from an intercooler also, but I'd start with the ATT first and then see if its still needed.

 

[NVW]

I think EGT is what killed your engine if you had your foot to the floor like that. Mine as it's equipped would get too high EGT in less than a minute with WOT and a load on hilly ground.

The lowest price I've found for ARP head studs is from cnc motor sports $122 part no. 130-4062

 

[Matt Bachand]

If you were pushing this truck that hard with no EGT gauge who knows how high EGT's you were running... You may have sealed its own fate doing that.

 

[Matt Bachand]

Jinx!

 

[WarWagon]

If you were pushing this truck that hard with no EGT gauge who knows how high EGT's you were running... You may have sealed its own fate doing that.

:mad2: Could not get the time to finish the EGT probe install. Too many other repairs to do kept coming up… But she ran for weeks like this. Bad part is I knew I needed it installed.

Turbo back 4” exhaust and intake snorkel removed helped keep temps down some I am sure. .

 

[buddy]

With my high flow exhaust my EGTs never climb much over 900F preturbo with my foot to the floor even running uphill when boost climbs and sustained 13+ psi. Of course that just with the bed loaded an not towing, but when monitoring I will be at max fuel rates of 80mm3 for quite some time, until I get going so fast it feels a little dangerous.

Whether rebuilding or not get the ATT, or a Holset (which is not as bolt on). Its considerably better when pulling.

If you are rebuilding, splayed mains, new Scat crankshaft. Sure get the -.01" height pistons and if you have a block decked get some Cometic head gaskets that are 0.06" thick (this will be a 5 steel layer gasket vs 3 and about +.015"). You will end up around 19:1 compression this way. The ARP head studs. Have engine balanced and use a Fluidampr.

 

[Brooklyn Tow]

Or a Cummins swap!

 

[WarWagon]

Or a Cummins swap!

):h If the 6.5 can do the job... How much does the swap cost vs. just dropping in another 6.5 or fixing/upgrading mine if possible?

I am not that impressed with the Cummings as posted above. :nonod:

 

[Mudbath]

):h If the 6.5 can do the job... How much does the swap cost vs. just dropping in another 6.5 or fixing/upgrading mine if possible?

I am not that impressed with the Cummings as posted above. :nonod:

I love my 6.5 but it will not pull like the Cummins, you must have got a bad one. They are getting a 1000HP on the dyno if you've got the money and tranny to put it to the ground!

 

[davo727]

I have a 6.2 truck that runs good around the flat here, -

but when my project list gets around to building a 6.5 for towing its going to get a new forged crankshaft from peninsular diesel ( about $900 + shipping).

I cant stand the possibility of a weak crankshaft breaking a month after doing a several thousand dollar rebuild, along with the wasted effort.

Also Scat sells a cast steel 6.5 crank for about $450 that would be way better than an old stock one.



.

 

[Paveltolz]

To help understand the climbs he's got, there are about 3 big ones and about that many medium ones that I recall and they don't get better going back from Payson to Phx either.
Phx to Fountain hills is 3 to 4% for about 20 miles. 5 mile 'break' and then Verde River climb for 10 miles to the top of Sugar Loaf Mt hitting 6% most of the way. Drop 10 miles and climb out of Surprise for about 10 miles at 6%. Drop off the back of that and hit the final climb to Payson for what seems like for ever on your hands and knees (did I miss one WarWagon?). Now add 110 plus Summer temps... He's got a challenge.
My truck didn't like it a bit in October temps when I was running empty but with mostly stock everything and an air cleaner that probably could have used a change. Needless to say, it really hated the run up through Kingman with the bed full of tools and the U-Haul with 5K in it. Talk about limp mode.

 

[Detroit Dan]

If you're willing to spend the money for a rebuild, which aint cheap, then you should consider the ATT as part of the cost. It is the absolute number one thing that you are going to need. And it's cheaper than putting in a Cummins (with no G). I've driven some Cummins, and while it will pull all day year after year without breaking, it won't do it fast. Yes you can make it fast, but you are going to spend on top of the swap. And then the problem is a turned up Cummins is a transmission eater. So look at a few grand more for a tranny that can stand up to the motor. If you've got the money to tear down and rebuild the truck, maybe you should put that money toward a Dodge with a Cummins, and just do the basic mods. Or fix your truck and sell it and buy a Dodge. As much as I dont like Dodges, it is the easiest way to get behind a Cummins. Which will survive the kind of work you want it to do. Only problem is you'll be sitting in an uncomfortable, lousy riding POS.
Didn't catch what kind of weight you are pulling, but if it's 10k or more maybe you should look into a medium duty.

 

[Dave01]

While I've never driven a Cummins Dodge, a friend bought a late '90's dually and wasn't impressed with it towing. It will go anywhere, but not fast as others have said. He's had to do tranny work and more to get it in decent working order, none of these trucks run forever under load without spending money.

Like Dan said, I'm wondering if you need a heavier truck. I don't care how many parts you put in, if you have to run with foot on the floor for hours on end something will break. How much weight are you pulling? There are a lot of heavier duty trucks on the market, you might be surprised at the deals you can get. The downside is you have less of a daily driver, more of a work truck, but it sounds to me like that's what you need.

 

[Brooklyn Tow]

Sounds like you need 3500HD......15000 GWVR

 

[buddy]

Getting the 3500HD doesnt get him any more power that a 2500, just the suspension stuff.

If you hadn't already turned up the fuel with the screw on the IP that would net you quite a bit more power. Doing it with no pyrometer is kind of dangerous. And with the ATT or other larger turbo, it can provide greater air mass so you get more pulling power so your foot isnt to the floor. Also WMI would help.

 

[WarWagon]

Scale tipped 13860 LBS total truck and trailer loaded.

The hills are described well above. Best part is it is cooler as you go up. I am driving on snow up there on the roads now. But I would end the day in the 110 heat. Start early enough, 3AM, that it would be cool at night.

 

[Dave01]

So maybe 7,500 to 8,500 trailer weight? You should be able to set the truck up to handle that. Good advice given from the guys here, I know nothing about the ATT but from reading here it clearly does the job, lowers EGT while improving towing power.

 

[Matt Bachand]

Wow what a nightmare of roads! I'd be hating that run!!!!!!

 

[Paveltolz]

Wow what a nightmare of roads! I'd be hating that run!!!!!!

Sorry, I'mfftopic:

Actually, it's a nice run if you appreciate geology and observing the changes in vegetation and the variety of colors in the landscape. Scrub cactus give way to the Giant Saguaros; the valleys starting in Surprise have water, and therefore, Cottonwoods 70' or better with tall grasses carpeting the hillsides. Unobstructed views abound and rolling down into Phx at night is awesome. The road was mostly 4 lane the whole way (may be all the way now). Changes in weather only enhance the beauty but then there's the summer heat in the "Valley of the Sun" (and they aren't kidding) and that feels like hell and can joy of any drive. Opposition in all things I guess...like choices in trucks and or power packages, towing options, mods etc.
Back to the topic at hand.

I have to agree with the other posters.
Aside from the ensuring the A/C condenser and radiator are kept clean, cooling upgrades (with the right water pump), balanced cooling set up for the heads and the ATT, all I can say is perhaps backing off 5 mph or so would help. Often "Less is More" and / or "Slow is smooth and smooth is fast." Meaning less down time for repairs. You'd only be adding about 30 minutes to each leg.