D44's with a diesel

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Grand_Wag_85
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D44's with a diesel

Post by Grand_Wag_85 »

Planning on doing a Duramax swap into a GW to be a DD/tow rig. Will the D44's live behind the diesel? Stock height, stock tires, stockish LB7 or LLY with auto trans.
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Stuka
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Re: D44's with a diesel

Post by Stuka »

For daily driving the rear D44 would be perfectly fine (towing/hauling is where issues may come up). My concern would be the longevity of the front D44 with the extra weight on it. Ball joints may become a common replacement item.

And one thing to note, I don't think the engine will fit without a lift because of the axle to pan clearance. Stiffer springs would be wanted anyway to deal with the weight. But you can cross that bridge after the engine is in and you can check clearances.
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dodgerammit
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Re: D44's with a diesel

Post by dodgerammit »

Stuka wrote:For daily driving the rear D44 would be perfectly fine (towing/hauling is where issues may come up). My concern would be the longevity of the front D44 with the extra weight on it. Ball joints may become a common replacement item.
This. Having been on a Dodge truck forum, there have been plenty that have put a Cummins 12 valve (1200#ish) over a 44 with no issues even after a couple years in. However, the weight rating would concern me since a 44 is rated at 3500#. I would also say it depends heavily on the quality of balljoints in the axle.
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derf
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Re: D44's with a diesel

Post by derf »

They might live for a while but if I was going to the trouble of doing a swap with a big heavy diesel I'd be researching heavier duty axles than factory stock.

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Re: D44's with a diesel

Post by Nikkormat »

Put a 4cyl diesel in it to save weight, and pull 30+ MPG out of a Waggy.
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Re: D44's with a diesel

Post by Adventure_Wagon88 »

Nikkormat wrote:Put a 4cyl diesel in it to save weight, and pull 30+ MPG out of a Waggy.
What 4 cyl diesel would do that? Do you have any evidence to support this? I’m doing a 3.9 L diesel in my Waggy and expect maybe 19-22 MPG. I’ll be thrilled if I can squeak 25 out of it empty. Even if I was running stock tires I don’t think it would break 25 easily. I’m doing a TDI 1.9 in my XJ and that I expect to be right around 27-32. I’m just not sure 30+ is realistic with any engine in a Wagoneer due to weight/size/aerodynamics

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Re: D44's with a diesel

Post by Adventure_Wagon88 »

I went through this same phase of questioning for my build. What it came down to for me was weight on the front axle, and towing. I just didn’t want to have to worry about the axles all the time. You have to look too at what the factory engineered too. There are no 1/2 ton rated Duramax trucks. You’re only going to find them paired with a very stout full float 1 ron rear. Even if you don’t want your Wag to be much bigger, I’d plan on running a set of tons and a tire size you’d find on a stock duramax truck which will be a little bigger than the OEM wagoneer tire, probably around 31-32.5” tall. You can fit that with minimal lift/trimming.

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Re: D44's with a diesel

Post by Locked and Loaded »

I'd be more worried about the frame.
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Re: D44's with a diesel

Post by 230ohc »

There are 1/2 ton diesel options, that however excludes duramax, Cummins and powerstroke.
The 1/2 ton options may only result improvements in fuel economy, but so will an LS swap.
I know someone who is doing powerstroke on an early 60's international truck where he essentially is only using the bed and body mounted over a 2005ish 7.3 chassis with a shortened frame and custom rear drive shaft.
zero worries about what will or won't work.
This may be an alternative pursuit to my current diesel conversion.
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Re: D44's with a diesel

Post by rocklaurence »

A 1200 lb motor over the D44 knuckles is too much.
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Re: D44's with a diesel

Post by Stuka »

I just noticed the OP also said stock tires. Which being they are a 15" wheel will be Load Range C, which also won't handle the weight.
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Re: D44's with a diesel

Post by rocklaurence »

Allison transmission will probably need floor clearance
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Re: D44's with a diesel

Post by Mass »

Old thread with recent posts..
I'm running D44's with a stock 6bt.
No issues yet and it's been about 4 years. No ball joints or broken parts (yet). I do have a 4" lift though.
I don't think the added 200-300ish pounds per side makes a huge difference for how I drive.
I also don't do any crazy off road/rock bouncing crap or tow more than 3,000 lbs (The frame is what I worry about)
It's all about the mileage, WMO, and reliability :)
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Re: D44's with a diesel

Post by Mikel »

Adventure_Wagon88 wrote: Mon Sep 24, 2018 4:01 am
Nikkormat wrote:Put a 4cyl diesel in it to save weight, and pull 30+ MPG out of a Waggy.
What 4 cyl diesel would do that? Do you have any evidence to support this? I’m doing a 3.9 L diesel in my Waggy and expect maybe 19-22 MPG. I’ll be thrilled if I can squeak 25 out of it empty. Even if I was running stock tires I don’t think it would break 25 easily. I’m doing a TDI 1.9 in my XJ and that I expect to be right around 27-32. I’m just not sure 30+ is realistic with any engine in a Wagoneer due to weight/size/aerodynamics
I know someone with a 4BT in a Wagoneer (lifted) and he gets 22MPG.

My M715 hybrid (4BT with 1ton drivetrain) gets about 18MPG.
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eggman918
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Re: D44's with a diesel

Post by eggman918 »

After a overhaul and compounds I have been averaging 17 +/- .5 over the last 30,000 miles this is in a tall truck that weighs 8,000 unloaded and in a state where 75 is the interstate limit..........$.02
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Mikel
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Re: D44's with a diesel

Post by Mikel »

Mass wrote: Sat Sep 07, 2019 3:49 pm Old thread with recent posts..
I'm running D44's with a stock 6bt.
No issues yet and it's been about 4 years. No ball joints or broken parts (yet). I do have a 4" lift though.
I don't think the added 200-300ish pounds per side makes a huge difference for how I drive.
I also don't do any crazy off road/rock bouncing crap or tow more than 3,000 lbs (The frame is what I worry about)
It's all about the mileage, WMO, and reliability :)
Very cool. How's the power and MPG?
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Re: D44's with a diesel

Post by Grand_Wag_85 »

I see there is a 6SPD auto used in the newer trucks that can be made to work behind the 12V. Is there a noticeable difference in MPG for the extra 2 gears?
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eggman918
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Re: D44's with a diesel

Post by eggman918 »

Grand_Wag_85 wrote: Sat Feb 08, 2020 8:15 pm I see there is a 6SPD auto used in the newer trucks that can be made to work behind the 12V. Is there a noticeable difference in MPG for the extra 2 gears?
I would expect any of the newer autos will require a stand alone controller so if you go that route I'd start my search there............$.02
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1968 F-250 CrewCab Cummins 4BT, ZF-5, NP 203/205,TruTrac's front/rear.
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BaldBeardedBastard
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Re: D44's with a diesel

Post by BaldBeardedBastard »

I went with the Cummins 2.8. It's about the same weight as a 360. I'm keeping the Dana 44s, just regearing. For a standalone controller for the trans, I would recommend Compushift- it can work with a bunch of different trans options that are electronically controlled.

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