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I don't know who, if anyone, here reads JP Magazine but in one of their recent issues (either Sept. or Oct.) I believe the editor had an article where they were talking about Jeep offering diesels in their vehicles. The article went on to mention that they were aware of the bread truck Cummins swaps, but down played the swap due to the vibration factor such an engine would have. I don't have the article in front of me to quote, but I can post it tonight. The confusing thing is that they featured an older J-truck a couple issues before that with a 6bt, citing it was pretty cool someone shoe-horned a diesel into that vehicle.

I've been researching Jeeps and 4bts/diesels since I have neither, but want both. Ultimately, swapping a Jeep (VM/Detroit Diesel) 2.8L CRD engine into a Wrangler would be pretty sweet, but I believe it was only offered for 2 years in the Liberty. Chances of finding one is pretty slim.

Is the vibration from a 4bt in small platform like a Jeep really that oppressive? I am not expecting it to be like riding in a Mercedez, but the article made it sound like your were going to lose your fillings if you had a 4bt in a Wrangler! Let's assume you did all you could to minimize vibration (with the motor mounts, etc.)

I'm just wondering what everyone's thoughts are? I'm more interested in a rough and tumble, simple, diesel powered vehicle that a Jeep-type platform would provide. It would have plenty of power, torque and could get mileage numbers approaching 30 mpg on the highway, something that Jeep didn't really do very well with the CRD in the Liberty (claimed 27 mpg highway).

Thanks!
 

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They rattle more at idle/shutdown than running on the road. It's just the design of the engine & the type of injection they use. Direct injection engines tend to clatter & vibrate more. Indirect-injection engines not so much, and the new pilot-type injection's hardly at all (High pressure, common-rail setups)
 

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I would question how many 4BT conversion Jeeps Mr. Know It All has ever ridden in or driven for any length of time? Dozens? Hundreds? ONE?

Sure, vibration is a concern and it can be a problem, but to me minor. I laugh to myself [sorry if I offend] when I see somebody wanting a Jeep like a CJ type with power this, automatic that, cushy this and padded that, climate control air conditioning, electric windows, power seats, cruise control etc. Seems to me that somewhere along the line this person is missing the point, by a country mile. Just my opinion, but a Jeep is supposed to be a Jeep, right?
 

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I have the article in front of me as I write this. Here is the quote that I believe is being talked about. (Oct. 07 page 6)
"It's slow, heavy, low-revving, Smokey, loud, and vibrates like the bed in a cheap Las Vegas hotel."
I must agree with JimmyD and DarylB, not to mention I am an old school heavy diesel mechanic by former trade.
I really can't disagree with any of the above comments as they do accurately describe the stock 4bt engine. Granted the engine can be turned up for more power, the engine is all cast iron so it is going to be heavy, smoke can be minimized, sound can be abated, revs can go higher with a different governor spring, and yes it rattles much more that a modern day engine, but no more than a comparable engine of the same vintage. I do get a little laugh at those who want 2007 gas engine sound levels and vibration out of a diesel engine that is close to 20 years old. It is what it is, if you don't like it then look elsewhere for a more efficient engine whatever that definition happens to be.
Like JimmyD said I mean no offense toward anyone with my comments.
 

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do a google search for " 3.3 cummins jeep "
 

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I too read the article in the magazine. I used the van mounts in mine and turned the idle up just a little and now it doesn't vibrate at idle and on the road it has very little vibe. Actually the tires (35's) vibrate more cause of the tread. The only time the jeep is noisy is when I am next to a building or something that echos the sound. All in all it's a great engine for a swap and a huge step up for a cj
 

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I don't know who, if anyone, here reads JP Magazine but in one of their recent issues (either Sept. or Oct.) I believe the editor had an article where they were talking about Jeep offering diesels in their vehicles. The article went on to mention that they were aware of the bread truck Cummins swaps, but down played the swap due to the vibration factor such an engine would have. I don't have the article in front of me to quote, but I can post it tonight. The confusing thing is that they featured an older J-truck a couple issues before that with a 6bt, citing it was pretty cool someone shoe-horned a diesel into that vehicle.

I've been researching Jeeps and 4bts/diesels since I have neither, but want both. Ultimately, swapping a Jeep (VM/Detroit Diesel) 2.8L CRD engine into a Wrangler would be pretty sweet, but I believe it was only offered for 2 years in the Liberty. Chances of finding one is pretty slim.

Is the vibration from a 4bt in small platform like a Jeep really that oppressive? I am not expecting it to be like riding in a Mercedez, but the article made it sound like your were going to lose your fillings if you had a 4bt in a Wrangler! Let's assume you did all you could to minimize vibration (with the motor mounts, etc.)

I'm just wondering what everyone's thoughts are? I'm more interested in a rough and tumble, simple, diesel powered vehicle that a Jeep-type platform would provide. It would have plenty of power, torque and could get mileage numbers approaching 30 mpg on the highway, something that Jeep didn't really do very well with the CRD in the Liberty (claimed 27 mpg highway).

Thanks!
Check out my website the link is below. I now have around 3000 miles on my conversion. Sure it Vibrates (it's a diesel) it dosen't vibrate that bad. My wife rides in it and she doesn't complain about it. I am unable to get my milage over 20. (I like power and smoke) I have my pump turned up and also have turbo modifications. (14cm3 exhaust housing and a 54mm compressor with a 4" intake and a 2.5" tube from turbo to aftercooler intake. My last tank driving pure city driving with the A/C (living in Cancun A/C is a must) I averaged 16 mpg. My trans is the origional and my rear axle is a 3.73:1 with 33" Tires. I am getting ready to change that to a 4.10:1 Rear with 35" tires.

I don't think the people from JPMagazine really have had the chance to ride in a converted Jeep with the 3.9L cummins. I would invite them to come and check it out....
my .02 worth
 

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I know mine's exactly what I wanted out of it.
 
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