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Just finished driving a Dovebid Frito Lay van back 200 miles to my home...that was more work than I anticipated!!!:puke: The van would only run about 50mph. This was real hard to deal with since I am used to my 2000CTD with the 24v 6BT. The good side is the engine seems solid and no problems. I am not a diesel mechanic so I have a lot to learn. This 4BT is to be the doner for my '72 Jeep Commando so I have a couple of questions. First off, I would like to keep the T400 automatic since my Commando came with the T400. The Jeep had the adapter for the AMC motor that came in it and the tranny bolt pattern is different, but shouldn't a good tranny shop be able to mix/swap the two transmissions and make everything work? Second, is there any reason to try and correct the tilt that these engines had when they are sitting in the chassis? Is there any affect on the amount of vibration if the motor is 100% vertical? Reason I ask is this thing vibrated like:pissed: when at idle. I expect this motor to vibrate and be loud, that is part of the reason I chose it for the Commando, but If there is anything that will lesson it, why not? Anyway, this is probably my first of many posts.:smile:
 

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If you are swapping the 4bt/TH400 into the Commando, do this:

Have your tranny shop of choice swap the output shaft from the Commando into the 4bt's TH400. Voila! Now you have a 4wd TH400 that fits the 4bt. SHouldn't be a big deal, since you're having that TH400 rebuilt anyway, with proper valve body and clutch mods, RIGHT? and you're going to run a nice big cooler on it RIGHT????

Thought so. :biggrin:
 

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Yes, I am definately going to have it rebuilt to handle the 4BT for a while. It needs attention any how, that is one of the reasons that Frito Lay auctioned it off, the front seal leaks! I kinda thought that the tailshaft would have to be changed. What about the tilt of the motor? Any reasons to mess with trying to staiten it up? Thanks.:smile:
 

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Yeah, I had a '70 Jeepster, and I finally found the '72 to replace the other. Nice looking Jeepster in the pic, what year is it?
 

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The tilt of the motor hurts nothing. It is better to have that, than to have the trans starving for fluid. And the Commando 400 to dana 20 trans adaptor uses a regular short 2wd car output shaft, so if you have one of those transmission's handy, you are in there.
 

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The only reason I would want to staiten the motor is for looks. But, if it doesn't hurt anything, I have other things to focus on. Thanks.
 

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Not a flame but you gotta change that front end grill and fenders to the true commando style.


It's beggin for it ...
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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The only reason I would want to staiten the motor is for looks. But, if it doesn't hurt anything, I have other things to focus on. Thanks.
By keeping the tilt you move the oil pan away from the front diff, assumeing your using a right side diff.
FYI, The transmissions used in the P30 vans are actually THM-475, which is the T400 with diesel converter and maxxed out clutches and a sitffer oil pan
 

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I ran my last cruiser with the Cummins tilt, it was fine and was actually good, lowered the turbo for better firewall clearance, moved the pan away from the diff.. I don't know TH400s but I believe the rear housings are interchangable and thats it and you have 4WD? Also, for what its worth, the bread trucks are TH475s, heavy duty TH400's.. :smile: I drove my bread truck I think 400-something miles home, across Wyoming! Same thing, 50-55 mph, slow.. :smile:
 

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Discussion Starter #11
Berg, the '72 is the Commando style, what is called the Bullnose front end. I owned a '71 with the Jeep style grill at one time. The Bullnose kind of grows on you, especially with 33s and a 4BT!
 

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Discussion Starter #12
Dieselcruiserhead, well glad to here that my P30 was about normal. Is the top speed pretty much controlled by the govenor spring in the pump? Also, it was not discernable to me if the turbo was actually kicking in. I couldn't here the wistle at all. When I finally get the body scrapped off of it I will start investigating the motor and turbo condition. Did you scrap the body on yours? What method, sawzall, carbide blade? Thanks.
 

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Never scapped mine, was too lazy/busy at the time, got about $700 for it I think by putting it in the paper for two months, everntually a guy made a dually out of his Dodge and the rest became a chicken coop :)

Yes they are governed about 2300-2500 rpms as far as I can tell... 55, maybe 60, 65 going down hill. Very slow.. I had a head wind the whole way and it actually had a little trouble keeping up with the wind so I bumped up the full power screw a quarter turn and it smoked a hair but did the trick. I messed with the governor too but could never get it to go much faster, but I will work with that once I get it in the land cruiser...

Around town though, even stock, my bread truck sure was zippy though IMO.. I can't remember if I could hear the turbo spool up or not. If not, honestly no big deal as you will probably want to replace it with something peppier anyway or at least do some mild modifications to it. For ~$160 bolt on smaller housing, it is night and day and I recommend it to anyone... See the thread in the performance section.. Maybe I should make it a sticky :)

Anyway, good luck! I love old Jeepster Commandos also, was almost my first car, too expensive but man I wanted it! :)
 

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FYI, The transmissions used in the P30 vans are actually THM-475, which is the T400 with diesel converter and maxxed out clutches and a sitffer oil pan
The TH475 is ACTUALLY the heavy duty version of the TH400. It has a different converter design (and for the Cummins, probably something else), straight cut gears, a bigger pan, and some other internal differences I can't remember.
Commonly found in big trucks, with e-brakes mounted to them. They are not just for Cummins vehicles.
 

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Also different governor, no vacuum modulator, and different valve body assembly so it's usually only interchangable with it's designed application.
 

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I got the back half of the body of mine off with a gasoline cutoff saw and a Bobcat to rip it off of the frame....It took me about 15 mins. :grinpimp:

 

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Discussion Starter #18
Savage, that looks like the quickest way to go! I need to be able to get the aluminum to the scrap dealer though, so I will have to cut mine up a little more.
 
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