Cummins vs. Powerstroke? I need help!

[LYNCHMOB]

Can anyone help? I want a cummins turbo or powerstroke diesel in my '82 Cherokee. I've read most of the threads and was wondering if anyone has put a cummins or powerstroke in their FSJ? I don't think I've seen this done. Would it be easier to buy a donor and put the Cherokee body on the diesel frame? I would prefer and older diesel with mechanical injectors and auto transmission. Any advice excepted.

Thanks
Ryan

[Brad W.]

diesel + auto = suck

If you want an easy swap, look at the 6.2L GM conversions on the board. Otherwise, I'd recommend a body swap, because I think a cummins would mangle a stock FSJ frame in short order. You'd need some heavy duty mods to make it live.

My personal preference: Gen 1 dodge diesel pickup... why:
*cummins/5-spd (be sure not to get a getrag tranny, it has to be an NV-4500 to be good)
*frame capable of handling the motor power & weight
*NP-205 standard equipment
*one ton axles (D60/D70HD or D60/D80 depending on model)

Just swap on the cherokee body, move the rear axle to fit the chero wheelbase, and lop off the extra frame in the rear.

[Stuka]

A 6BT wont fit very well, takes a sawzal. A 4BT cumins fits geat, and the weight is more manageable. A powerstroke, weighing in at around 1100 pounds is a bit heavy (same weight as the 6BT).

[TPICherokee]

diesel + auto = suck

I have to disagree. I have a friend that has a 1992 (old body) Dodge with the 12V Turbo Cummins w/ an automatic and his Dad has a 1994 (new body) Dodge 12V Turbo Cummins w/ the 5 speed. The 5-speed takes time to shift and the turbo spools down so it takes a few seconds to spool back up whereas the automatic shifts fast enough to keep the turbo spooled up and is A LOT faster.

Now, I don't know the strength of the Dodge automatics but I do know that he has 125,000 miles on the original tranny and it works fine...

Just my .02 cents.

Brent

[Brad W.]

He's lucky. The dodge autos are only surpassed in sucking by the ford autos. The Duramax are having problems with the allisons breaking too.

The Dodge autos suck because they dont pump fluid in park, so they boil themselves to death. The Fords are just a pathetic excuse for a transmission, both in strength and in quality control of factory lemmons. I've seen a new ford eat 3 in 2 months, I know the owner. If you make any kind of power upgrade, kiss it goodbye. Unless you plan to spend a ton of money on an ATS transmission, I would advise you to steer clear of the autos.

The design of an automatic is not made to handle the massive peak torque of a diesel, especially not with the torque multiplication that goes on in an auto. Manuals hold up far better because they are just parts machined from solid metal, and using bearings. Autos are far more complex with all the clutches, bands, springs, valves, fluid pressure circuits, etc etc, and that design is just not optimum for a motor with as much brute strength as a diesel.

[Brad W.]

I'd also advise against the powerstroke for simplicity and practicality.

The 12v cummins is mechanically controlled, is a very easy swap, does not have so many sensors, glow plugs, electric head gaskets (yes, the 6.0L ford has sensors in the head gaskets), and so on. The Cummins is an SAE pattern bellhousing, IIRC, so you can use a bigger truck tranny with the right housing &/or adapter ring. An auto from a industrial truck would hold up far better than the light truck transmissions do now (think bus autos).

If you want this to be easy, put a 4bt in your chero... they come in bread trucks, etc. and can use the NV-4500 or a TH400 (with diesel valvebody). They dont make nearly as much power as the 6bt (still have plenty, dont worry), so they won't destroy automatics the same way.

[rustywagoneers_com]

used to work in an international dealership

you do NOT want a powerstroke

4bt would be dandy

6.2 would be the cheapest and easiest

you will be better off with a donor truck

lots of nickel and dime stuff otherwise..

peace
Dave

[rockjeep44]

Anyone that gets a Diesel with an auto should be pooped on.

[boss6021]

Anyone that gets a Diesel with an auto should be pooped on.

Hehe, thanks for the laugh. I agree, super beefy auto, or solid manual.

Mike

[Stuka]

The turbo should not spool down when shifting a manual diesel if driven correctly.

Autos are great for city driving in little cars, not work duty. The whole design of an automatic is ineficient. You use mechanical energy to turn a hydrolic pump, then you convert that hydrolic energy back into mechanical energy... WTF?! Autos suffer from heat issues as it is, much less with all the torque of a diesel in front of them, and the weight of a heavy vehicle behind them. All the diesel pickups around here go through transmissions about every 50-60k miles on average, some sooner, some later. Especially the newer ones with more power or with mods done to them.

[The PIG Smith]

It's up the reader of the info in the following link to decide if it is fact or fiction.

http://www.problematicpowerstroke.com/

I know of several folks that own 7.3L Powerstrokes and love them.
From what I read and understand, I would stay away from the newer 6.0L Powerstrokes.
I almost bought a early 90's model Ford 7.3L Powerstroke, but instead bought my '99 WJ.

I've been studing Diesel engine swaps into FSJ for some time now.
By far the easiest swap is the GM 6.2/6.5.

There are a few members her that have perform this swap and I've have the following prepared notes to share with you.
This a post I continue make at Diesel Swap Questions and each time, I try to add a little something to it

************************************************** *********

Lot's of posts on this topic
I am sure I could found more, but I stopped at these links:

My 1990 Grand Wagoneer 6.2 Diesel project

6.2/6.5 diesel owners...

3.9L 4bt cummins

Diesel

My 6.2 Diesel GW

non turbo 6.5 Diesel on E-bay

Project update...

6.2L Diesel in a J20
Here are OhioJ20's comments from this post made on February 20, 2005:

Alright guys!! I'm in NE Ohio, close to Akron. The J20 got her 6.2 two years ago. It came from a 1984 GMC Van. It had the TH 700 tranny, but I didn't have the money to buy an adaptor for it to my t-case.

Alright, we removed all the electrical wiring that was for the engine, glow plug wiring, wait to start light, water in fuel light, etc. I also used the motor mounts, but had to make new frame mounts to put on the J20. We used the ignition wiring for the J20. Oh, took out the glow plug relay also. Wiring wasn't that bad, and no polution crap to worry about. The motor fits in snug around the heater box and the brake booster. We did use the Jeep brakes, as GMC uses hydrulics for brakes, but wouldn't hurt to have a belt driven vaccuum pump as well as the gear driven one.

Now, the 6.2 has the same bellhousing as a Chevy 350, as for the bellhousing a bought from a bone yard was for a 350. Now, we had to get an 1/4" steel plate to make our own adaptor for the bellhousing and the T-18. Luckily my cousin is a true machinist. So, that saved the money from Advance Adaptors, which want $300 for the same thing.

The great thing is, I can access the glow plugs from inside the fender, and it is ALOT easier than changing spark plugs from a AMC 360!!

As for how I like it. I LOVE it when it is above 45 degrees out! If you don't plug it in when it gets colder, it is a pain to start. Also, you don't have the room for the two batteries GMC uses. Need to get the biggest cranker you can squeeze in there.

I also had to use the van's filler nozzle, or you couldn't fill the truck up with the stock jeep nozzle. I also had to cut out the area into the tank, to allow a bigger pipe to go in(diesel foams when filling). Another perk, I put in the van's 30 gallon tank where my spare tire goes, so I now have 48 gallons at 22 MPG, you do the math!

Towing: It doesn't take off like some madden woman, but tows great. It did get hot on a real long grade, but didn't over heat. I also used the stock AMC 3 core on it, just had to get the ports changed. I would recommend a 4 core, that is what I have for the GW. I also bought an electric exillery fan to use to prevent that on the J20. The gearing in the J20 and the T-18 is perfect for a 6.2 I will get pictures of the set up soon, the J20 is covered up for the Winter so Ohio Salt doesn't eat her up!

Now, the GW is a work in progress, I have the motor, but I am currently in the process of body work and paint. My plan is to use the TH 700 from the van, but I got a TH 400 that came with the Suburban for the GW. My only concern is the weight of the motor on the front axle of the GW.

Now, if I left anything out, let me know or feel free to ask more! E-mail me if you want at [email protected]

There are two members here that have GM Diesels in their FSJ
OhioJ20 has a 6.2L in a J20 Pickup truck
He is also working on a 6.2L in a 1990 Grand Wagoneer

DieselSJ has a 6.5L Turbo in his 1987 Grand Wagoneer

FSJeeper has been involved in several of these 6.2/6.5 swaps over the years
Currently he has a fresh cherokee WT frame loaded with a built Turbo 6.2/6.5, eaton fuller gearsplitter/OD, SM465/doubler NP203/205 on built one tons.

The following is a reply that FSJeeper made about I comment I posted:

I believe it was you that suggested that a person could get an easy 300 horsepower from a 6.2

Well, not easy to get 300 HP because it requires a complete rebuild and some expensive parts. Following the 6.2/6.5 page GM diesel buildup, I went with the penisular teflon/ceramic pistons with 18 to 1 compression ratio. BD cam gear drive with advance, 6.5 heads, J series intake, bosch glow plugs, upgraded injectors and injection pump, etc., etc. On top of that, the engine was blueprinted as much as that can be done. Heads flowed, rotating assembly lightened and balanced as an assembely including HB and flywheel/pressure plate. Max torque and HP at at 1900 rpms. A build like this costs several thousand dollars.

It got 20 MPG in a 10,000 lb decked out M715 (4.56 gears) and I expect about 25 mpg in the Cherokee with the OD and 3.54 gears. Should be chugging along at 1900 rpms at 70 MPG and with the gear splitter/OD and doubler setup, I have 32 speeds.

Downside of the diesel is the inability to spin high rpms for sand and mud. The doubler is for the 4 to 1 low range to best utilize the 3200rpm redline the diesel has. Theoretically sitting on top of 3000 rpms or so and the 4 to 1 low should take care of the sand and mud issues a diesel norammly has.

Search on their names and their posts will provide lots of excellent info!

[FSJeeper]

A 6BT wont fit very well, takes a sawzal. A 4BT cumins fits geat, and the weight is more manageable. A powerstroke, weighing in at around 1100 pounds is a bit heavy (same weight as the 6BT).

Nope, not correct. No sawsall needed. 6BT will fit a FSJ engine bay with no mods. TexasJ10 was recently out at my ranch and saw an example of a supurb 6BT swap in an M715 of a buddy of mine. No body mods whatsoever. Custom radiator is built to fit within the core support for front space. As for the intercooler, you use the air to water type cooler like the CAT dozers have that bolts on top of the valve covers. Frame needs beefing and I think a Dana 44 front is a bit light duty for that kind of weight and torque though.

Without a doubt, the cheapest, easiest, and fastest way to diesel in a FSJ is the Chevy 6.2/6.5. A few mods will bring the engine up to good horsepower and fuel mileage is over 20mpg. It is the lightest diesel and weighs about the same as a big block Chevy engine. Adapter parts are available from lots of sources. Fairly easy swap.

[JohnIL]

What about the 727 auto? Would it hold up to a diesel swap? I've thought about installing a 6.2 with an advanced adapters small block chevy adapter in front of my 727. Would that work?

John

[The PIG Smith]

It is the lightest diesel and weighs about the same as a big block Chevy engine.

I agree that of the domestic Diesel engines that a person could choose to swap, that the 6.2 is light, making it very swappable.
Maybe the Cummins 4BT weights close to the 6.2, but somehow I think it might be slightly heavier.

Another light weight Diesel is the Chevy Duramax.

Copied and pasted from the Duramax Diesel Site,

http://www.duramaxdiesel.com/01_features/sub04.htm

The Duramax 6600 weighs only 836 lbs., thanks to the use of aluminum in key components like the cylinder heads,
crankcase, accessory drive brackets, intake manifold and flywheel bell housing.

While there are those that either love the Duramax or hate it, it is smaller and much lighter than the Cummins 6BT and Ford Powerstroke.
Also, the 2005 model Chevy Duramax produces more horsepower in raw stock form than either the Ford or the Dodge.

Another plus is the Duramax is offered as a Crate Motor. (but very difficult to locate and very high priced)
So what? What makes a crate motor special?
It is marketed as a re-power option and come with a stand alone computer.
The stand alone computer and wiring harness make swapping much easier.

Regardless of what is said, the Allison A1000 automatic transmission is the strongest, best designed and engineered Auto tranny on the planet.
Yes, it has had some teething issues, but just like the 700R4 and another similar first generation item, but most have been solved.
Nothing is perfect on Revision 1.0

The Duramax and Allison A1000 still use the tried and trued standard Chevy bell housing bolt pattern,
I've read articles where hot rodders have installed A1000 behind killer 572 Big Blocks in ProStreet pavement pounders.
Which also means, most all standard Chevy trannys will bolt up to a Duramax.
It a person had deep pockets and wanted to build an ultra duty Powerglide and install it behind a Duramax, it could be done.
Crazier things have happened.

Disclaimer

A lightweight Diesel engine is a relative term.
I am sure, if someone wanted to, they could take a 3208 V8 Caterpillar from a Freightliner and somehow make it work.

For the purposes of this discussion, swapping a Diesel engine in a FSJ, my definition of a lightweight Diesel engine is one that can be adapted to a
FSJ's engine bay, frame and suspension without heavy modification.

A heavy weight Diesel, like a Cummins 6BT and the Ford Powerstroke, would require a Dana60 front axle, frame strengthening,
stronger front springs, possible heater box relocation, possible some creative radiator solutions.

Now, I am saying that a Cummins 6BT and the Ford Powerstroke can not be swapped into a FSJ???...by all means NO!
There are folks here that have this type swap as a project or have completed this swap.
My comments should be taken as a 6.2 is by far the least complicated Diesel engine swap a person can perform.
Which IMHO, also means less time in the shop and less $$$ for the overall swap.

I have my flame suit on and am braced for rebuttals.

[LYNCHMOB]

Would it be easier to find a 4x4 diesel donor with running Chassis and put my Cherokee body on it? Can the 6.5 with turbo do what the cummins or powerstroke can do(within reason) and be as dependable as the cummins? These are all questions(and many more) that I have before I make up my mind on what diesel swap or change I want to make.

Thanks,
Ryan