Build a diesel jeep wrangler

I bought a 1991 VW jetta non-turbo diesel for exactly that reason. I love my diesel truck, but, for commuting around town or even trips where i'm not hauling anything I really like my little jetta. I've driven it across the country many times, to texas, florida, missouri and everywhere in between and it has never let me down. The 91 is nice because it has more creature comforts than previous models, yet, it is still a non-turbo mechanically injected diesel. It's less than 60 hp so it's not fast, but it will cruise just fine at 75-80, and has decent enough acceleration that, once you're used to it, is perfectly manageable; I may not be passing everyone, but it keeps up with traffic just fine. Being a non-turbo I get great mileage, 50-60 on the highway, and close to 50 in town. the '91 is a nice model with decent passenger space, a huge trunk, and still maintains the drivetrain simplicity of earlier model year jettas. When I was looking for a smaller diesel vehicle to drive daily instead of my truck, I specifically sought out the '91 model year jetta; I bought it in mint condition sight unseen, picked it up and immediately put over $1000 into it to bring it to like new condition with regard to handling and durabilty. I replaced the battery, water pump, head gasket (added studs), all belts and hoses, bushings, cv axles, ball joints, struts/shocks and mounts etc. The car handles like new, drives like new, and looks like new for less than $2200 total cost. Parts are very cheap for '91 mark II jettas which allows you to replace things without feeling too badly. I also have a 1995 E300 diesel that I absolutely love, but would not reccomend as a daily driver for great mileage (parts are expensive, needs special tools to work on, and averages only around mid 30's mpg instead of the jetta's 50+ when properly tuned).

BTW, if you're looking seriously at putting a small diesel in jeep etc. and have a goal of reliability and good mileage, I would avoid going after too much power. In fact, I would avoid anything with a turbo, it reduces your fuel economy (not by much, but if you're not going for power, why bother). With an N/A diesel, you don't have to worry about EGT's, you get better fuel economy and generally better initial throttle response, and you've eliminated an additional area of failure. Without spending some dough, the jeep's drivetrain will be destroyed by a diesel producing much power or torque, unless you're looking for a money pit/big project, stick with a small, non-turbo diesel producing less than 100hp and you'll be better off.

Coalfire wrote:

AA130FIREMAN wrote:I have a diesel in my truck, ford 7.3 crew cap with 8 foot bed, to big for every day use, 17mpg on the interstate or short trips, the 4.10 gears eat alot at higher speed. I figure a jeep with overdrive and 3.08 gears with the 4 cylinder should do 30+ mpg, and sound good doing so

Would be kind of cool. What do these motors get in there stock applications? I know a guy that put some 3.7l diesel i think a small detroit in a dakota. Then he had overheating problems, and not enough room for an intercooler to make it really efficient. How much do these 4bt's weigh??? that is the other thing to consider that is a lot of extra weight in the front of a wrangler.

The motors are in generators, backhoes, old ford and chevy bread trucks(step vans). The engine(800lbs) is 200lbs heavier than the factory 6 in a jeep. The factory radiator will handle the diesel(runs cooler)intercooler from dodge diesel in the jeep, and their is a crankshaft exiter ring that wakes up the factory wires for the dash and tactometer. They need a 4 " lift kit to clear the oil pan from the front differential and a vacuum pump for the power breaks. The fuel tank needs the fuel pump removed. As far as transmission, the factory will work with adapters, but I talked to someone that did one, he used all dodge cummins(will handle the torque) bellhousing to transmission and an adapter on the rear of the trans for the factory jeep transfer case. New motor mounts that weld to the frame for the engine,factory mount to the transfer case.

A jake break would be boy the neighbors would love me for that

This sounds interesting, what are these guys that have done this actually getting for fuel milage. I think 30+ is a stretch. Maybe more around 21 is the answer. Just do it for fun don't say to save fuel. I could see this thing costing $10K with a donor motor and a donor jeep, lift kit, and everything else. for $10K you can buy alot of fuel . I know someone that bought a motorcyle for $9000 dollars. They bought it to save gas money they only put 9k on there truck a year and now they put 2500 on the bike, sooo the 2500miles of savings at 13mpg@$4per gallon= $769. But now they put that on the bike 2500/30mpg@$4per gallon= $333. $769-$333= So They are saving $436 per year, wow it will take 20years of that fuel savings to pay for just the bike

Don't take this post as negative. If you are doing this project for fun than by all means do it. if you are doing it for fuel/money savings I think you will be disappointed. from your original post if you were looking at a jetta I would assume it is for economical reasons.

On a pleasant note someone came into the shop a month ago with a yukon denali he swapped a 4bt into it and was getting 23mpg on the highway, it was an awesome setup, and it sounded nice when he was pulling out of the drive


Best of luck, Eric

I believe 30mpg would not be out of range, coworker had one of the dodge truck cummins 6 cylinder with 3.55 gears and was a heavy 3/4 ton super cab and said he got 22mpg. With 3.08 in a lighter jeep sounds possable. I can see the cost of project would be expensive, but the longevity of the diesel engine should go for 300,000-400,000 miles. Like I said, I do like the diesel sound Find a jeep first, run it as is and look for a cheap diesel, possably free if I can find an aluminum bread truck for scrap metal price.

Economy? Go Berlin's route. Fun/Project build that jeep.

This guy put a 4BT in a 1990 Bronco.
http://www.ford-trucks.com/forums/98173 ... build.html

I thought there was a guy that put a 6BT in one also but I can't find the thread.

Here are some related links. I had a 1962 Willys CJ5. I almost replaced it with a CJ with a Perkins. There where some around when I was a kid.

http://www.jeeptech.com/engine/perkins192.html

http://www.allpar.com/mopar/perkins.html

http://www.jeep2diesel.org/

http://www.dieselpowermag.com/news/0607 ... ep_cj.html

[youtube]http://youtu.be/ZtkMNs1GAbs[/youtube]

[youtube]http://youtu.be/xXoZRe9cuZA[/youtube]

[youtube]http://youtu.be/zj03m49Z0IY[/youtube]

Check out this forum

http://www.4btswaps.com/forum/index.php

Apparently you can buy a 2010 Wrangler with a diesel in Europe. http://dieseldig.com/2010/03/17/not-for ... er-diesel/

I wonder why everywhere else on earth diesels are so readily available (to the tune of roughly 50% of all cars being diesel), but here in the good old land of the free they are not available?

The sheep are scared of diesels.

lsayre wrote:I wonder why everywhere else on earth diesels are so readily available (to the tune of roughly 50% of all cars being diesel), but here in the good old land of the free they are not available?

Could be if the fuel station in other countries only have 2 pumps, one will be diesel. Their is more energy in a gallon of diesel than gasoline, not refined as much. As far as in the usa, might it be the epa has some factor in not having diesel in cars, we might not be as free as we thing we are

AA130FIREMAN wrote:I believe 30mpg would not be out of range, coworker had one of the dodge truck cummins 6 cylinder with 3.55 gears and was a heavy 3/4 ton super cab and said he got 22mpg. With 3.08 in a lighter jeep sounds possable. I can see the cost of project would be expensive, but the longevity of the diesel engine should go for 300,000-400,000 miles. Like I said, I do like the diesel sound Find a jeep first, run it as is and look for a cheap diesel, possably free if I can find an aluminum bread truck for scrap metal price.

I really doubt you're going to see anywhere close to 30 mpg unless you drive no faster than 55 and gear it tall. I have a '05 Liberty CRD (still)... it could give a run to Smitty's Jimmy, let me tell you....and I think it might crack 30 if you drove it like a corpse. But, normal daily driving averaged low to mid 20's over 80k miles. I've seen a few 26 and 27 mpg tanks, but they are rare.

There is a company (Green Diesel Engineering) that offers both eco and performance tunes for the ECM and TCM which is said to improve mileage by undoing some of the boneheaded Chrysler programming as well as disabling the EGR (which I've done using an alternate electronic method). That might get it to 30 mpg, but you'd still have to drive it slow.

You would think that a 2.8L 16V common rail diesel would get great mileage, but unfortunately it's stuck in a 4000 lb. pig with the aerodynamics of a mule's backside and a 4WD system that is always spinning the axles and front diff. However, when I'm not fixing another under-engineered Chrysler part on it, it's a real nice vehicle to drive. Quiet, handles decent, and quick! 160 hp/295 lb.ft. is more than enough (way more).

Conversely, my '02 Jetta wagon routinely averages in the mid 40's and will hit 50 mpg on a highway trip at 70 mph with the A/C on. If I installed some Michelin low rolling resistance tires I could gain 5 to 10% more mpgs. I would hope the latest generation of tires have improved upon the OEM Michelins that came with the car because while the mileage was great, the wet traction was non-existant. I happily gave up some mpg's to get tires that wouldn't break loose in 3RD GEAR!!!

The '99.5 - '03 VW diesels had the "ALH" engine, which was turbo (VGT, not wastegate), intercooled, and had the Bosch VE distributor pump injection system. The '04 and up went to the PD engine (pumpe-duese) and those are known to eat camshafts. With proper maintenance, these engines easily go 300K, and some are past 400K. The A4 chassis (Berlin has an A2 chassis) is pretty bulletproof (and also pretty rustproof), although there are a few "VW-isms" that need to be watched out for. Overall, though, they are a durable car and high quality fit and finish. Parts aren't too expensive and widely available on-line. The best owner is one that can do his own work (as I do) because the dealer service department is the WORST thing you can do for a VW diesel. Some of the independant TDI "gurus" get much of their business fixing dealer service screw-ups such as cylinder head replacement from botched timing belt jobs....

My wet dream is a 6.2 Non turbo in a old shark body Corvette for something cool to drive that gets 30+ MPG

Sting wrote:My wet dream is a 6.2 Non turbo in a old shark body Corvette for something cool to drive that gets 30+ MPG

You can get 30mpg in a corvette from factory with tall ring and pinion gears. My 92 350 would do 28mpg on the highway (2.40 ish rear) not good out of the hole but would give for a good high speed persuit