Asking advice on engine/trans to buy...

[DreamWeaverBus]

Okay. I've read lots of discussions about lots of engines and transmissions that people favor or avoid. If you're not mechanically inclined, it's a lot to take in and try to absorb. So here is my post asking for people's opinions and advice on what kind I should shoot for. Sorry guys, I know it's all been said before...

I'm gonna start looking for a bus in EARNEST next month in March.

-$4000 is top budget to spend, obviously hoping to spend a bit less.
-I know I'd prefer air brakes.
-Tires under 5 years.
-Conventional dog nose bus. (Because they're easier to get to to work on and they don't run as hot as rear engines, right?)
-Min 10 windows, more is ok.
-Activity bus would be cool.
-Country route bus would be cool. (geared better right?)
-Minimal rust obviously.
-Full working mechanical order, obviously.

Highway gearing, locking torque converter, and a retarder would be cool...

So unless I'm missing something, that leaves the engine and transmission.

I know I want a diesel engine.
I NEED an automatic transmission.
going up to 70MPH would be super nice... without overheating...

So here's what I've been able to glean from my research:
ENGINES:
-DT466 Navistar - common engine, parts handy
-DT466E - what's the difference between the E and the no E?
-DT360 - same question? different DT engines?
-CAT engines - good engines, but repairs are costly and hard to find, prefer to avoid.
-Cummins engines - heard good things for a while then started hearing bad things, 8.3L good?
what about B5.9L (mechanical) and ISB (5.9L + 4.6L electronic)? Mechanical easier to work on, yay oor nay?
Other good engines to grab?

TRANS:
-Allison AT 545 - no torque converter, locks up
-MD3000 series - locked up torque converters
-MD 3060 - common trans, easier to work on?
Other good trans? I heard MST643 is also good...

I know everything else I want in a bus for sure, but the engine and transmission has me in over my head. Everyone has different opinions and experiences with different engines and transmissions, on the forum, in FB groups, on RV forums, etc. It's hard to formulate a solid opinion when you barely know what people are talking about.

How I plan to use the bus: Once converted, I plan to live in it full time, move out of state, (possibly mountains or nothern states) find a lot to rent or place to long term camp, find a better paying job, pay off student loans, then... I don't know. I might figure out what I want to do after I pay off my student loans while I'm paying them off. Might travel. Might float. Might plant my bus on homebase.

Kind of hoping to take my 2000 Dodge Caravan with me, pull it behind the bus when traveling, kept for everyday commute to work, drive the bus every week.

So with all that, does anyone have suggestions on engines and trans I should hope for, or avoid?
MY THANKS IN ADVANCE TO YOU ALL!!! I stand on the shoulders of giants!

[Twigg]

Couple of points:

1. All auto trans have torque convertors. Only the AT545 doesn't "lock-up". Locking up is a good thing

2. None of them are easy to work on and the preferred trans is the MD3060, but others are good too.

3. Absolutely nothing wrong with the Cummins engines. Indeed, the 8.3 is frequently spec'd as part of the most desired powertrain. 98 and earlier will be mechanical. Produced after mid-98 it will be the ISC (electronic).

4. Navistar DT466 and DT530 are also highly thought of. The DT530 is probably the cream of the crop, but also as rare as hen's teeth.

5. Don't dismiss CAT engines. They might not be preferred, but one in good condition will be everything you need.

[DreamWeaverBus]

That's awesome info! Thank you! *updates specs*

So, try to avoid AT545? I can't remember why you'd want a locking torque converter but I do remember I was like 'Oh I want one!'

DT530, rare as hen's teeth! LOL good one... But, cream of the crop, yay, but does rare mean harder to repair?

Would you prefer mechanical or electronic? I feel like people lean towards mechanical...

I won't dismiss CAT engines, everything I've read says they're great as long as they work. I'm trying to live by the 'ounce of prevention worth a pound of cure' thing..

If my bus doesn't have a retarder, I can get one installed right? I was checking out retarders, looked like they'd be handy in mountain areas...

[Twigg]

Originally Posted by DreamWeaverBus

That's awesome info! Thank you! *updates specs*

So, try to avoid AT545? I can't remember why you'd want a locking torque converter but I do remember I was like 'Oh I want one!'

DT530, rare as hen's teeth! LOL good one... But, cream of the crop, yay, but does rare mean harder to repair?

Would you prefer mechanical or electronic? I feel like people lean towards mechanical...

I won't dismiss CAT engines, everything I've read says they're great as long as they work. I'm trying to live by the 'ounce of prevention worth a pound of cure' thing..

If my bus doesn't have a retarder, I can get one installed right? I was checking out retarders, looked like they'd be handy in mountain areas...

A retarder is nice to have, but not strictly needed and most don't have them. The ones that do live in the mountains. If you plan on mountains you really do want to avoid the AT545 if possible. Any of the others will work.

DT530 is as easy to work on as all the other wet-sleeve engines (DT466, Cummins 8.3, etc). They can be rebuilt without removing them from the frame. None are "easy", but some are harder than others.

Electronic engines are easier to do some things to, but more complex in terms of sensors and things that can go wrong. However, pre-2004 they are generally reliable and well known. I have a mechanical Cummins 8.3, time will tell if it turns out to be better than the ISC.

[DreamWeaverBus]

Thank you so much for your insight. This was really helpful.

Yes I think it's best if I avoid the AT545, it's pretty likely I will go to the mountains at some point.

I feel a lot more confident about my engine options, and a lot less worried about the trans.

[o1marc]

This has me thinking now because I don't think the combo of motor/trans/body was actually made, or in such small quantities of special orders that they are now made of unobtainium. I've been searching prices on good used Cummins 8.3 and Navistar DT466's and find them for $3-$5k. I just found the correct body, already stripped, CAT3116, stripped to metal floor, already titled as MH. Needs injector sleeve work. $1000. So it might be cost effective for me to just build from scratch. Probably take 6 months to build anyways. I'm sure I could get a motor swap done in that time frame.

[Booyah45828]

So here's what I've been able to glean from my research:
ENGINES:
-DT466 Navistar - common engine, parts handy
-DT466E - what's the difference between the E and the no E?
-DT360 - same question? different DT engines?
-CAT engines - good engines, but repairs are costly and hard to find, prefer to avoid.
-Cummins engines - heard good things for a while then started hearing bad things, 8.3L good?
what about B5.9L (mechanical) and ISB (5.9L + 4.6L electronic)? Mechanical easier to work on, yay oor nay?
Other good engines to grab?

DT466 = 466 cubic inches, mechanically injected, Extremely reliable and also rebuildable. Different power levels that can be changed with hand tools.

DT466E = Same engine as before, but electronically controlled HEUI injection system (requires different head/pump). In stock form they have more power, but require a computer to modify. Not as reliable due to the injection system/electronics.

DT360 = Smaller version (360 cubic inches) of the 466. Similar to the 466 in most aspects, just less power.

T444E = some busses have this, it's an okay engine. Uses an early HEUI system making them somewhat reliable. Low power is the complaint had by most and I don't think it can be changed.

Cat engines = Talked bad about by most on here . The few I've worked on have been relatively trouble free. Parts are expensive because most are only available directly from cat(I've never had quality issues with cat parts fwiw). I avoid the later offerings from cat(3126/c7) because they use HEUI injection system, which isn't as reliable as mechanical systems.

Cummins engines = As with Navistar, They have more power in stock form electronically, but are easier to upgrade mechanically. They have issues that need addressed just like every other engine listed here. 8.3 is the big dog but the 5.9 works. I'm not a fan of the ISB due to injection pump issues but that can be remedied with a better lift pump and maintenance. The 8.3 is a rare option when it came to busses but is pretty desirable for its power and torque.

My preferences - Anything with a mechanical injection pump. You simply can't beat them reliability wise. But, those engines don't come with the auto trannies that have overdrive so you have to weigh your options.

[Booyah45828]

Originally Posted by DreamWeaverBus

TRANS:
-Allison AT 545 - no torque converter, locks up
-MD3000 series - locked up torque converters
-MD 3060 - common trans, easier to work on?
Other good trans? I heard MST643 is also good...

If you need an automatic, Allison is your only option.

The AT545 and MT643 options are the old style. They're mechanically controlled and you'll find them behind all of your mechanically injected engines, along with a few of the newer electronic engines. Both are 4 speed with no overdrive. The AT has no lockup converter which is inefficient and doesn't offer grade braking. The MT is stronger and has a lockup converter which makes it more desirable.

Allison converted to the "World" series transmissions which includes the 2000, 2500, 3000 and 3060. These are all electronically controlled, have OD gearing, and lockup torque converters. They're more reliable then the old style transmissions.

[Gdog 5651]

Allison 3060 is the desired trans and although I own a Cummins 5.9 with a P pump I think if I had My druthers I'd druther have a DT466 mechanical with a MT643 5.9 cummins w/643 Cat 3116 w/643 8.3 is great but very rare in a conv.cab bus No 8.2 DD (too old) and as far as I am concerned if it is out of warranty no smog diesel engines which rules out most world series Allisons also.

[Booyah45828]

Originally Posted by DreamWeaverBus

How I plan to use the bus: Once converted, I plan to live in it full time, move out of state, (possibly mountains or nothern states) find a lot to rent or place to long term camp, find a better paying job, pay off student loans, then... I don't know. I might figure out what I want to do after I pay off my student loans while I'm paying them off. Might travel. Might float. Might plant my bus on homebase.

So your main goal is to move away and then live in it full time? IMHO, you don't really need the biggest engine or the best transmission for something like that. A run of the mill 5.9 with an at545 would suit you just fine. Buy something that was maintained well so that it's reliable and then take your time getting there. I mean, dredman travelled for a while with a 5.9/at545 before he had problems (and even then, it was with the engine, not the at545 IIRC)

The big engines and transmission always seem to go for more $ because they're more desirable. But if you can score something reliable for 1500 bucks, then you're money ahead and can splurge on the interior, or pay down your loans. I think you'd be farther ahead going that route then buying a 8.3/MD3060 combo for 5 grand, just to park it until your loans are paid for.

[Whitespace Lifestyle]

What about 2008 Mercedes 7.2L 190HP
Any one know anything about these engines?

[DreamWeaverBus]

Originally Posted by Whitespace Lifestyle

What about 2008 Mercedes 7.2L 190HP
Any one know anything about these engines?

From what I've read, a Mercedes engine is a good engine, like a CAT engine, but like a CAT engine, expensive to repair.

[cowlitzcoach]

Originally Posted by Whitespace Lifestyle

What about 2008 Mercedes 7.2L 190HP
Any one know anything about these engines?

It isn't that the M-B is a bad engine. It actually is a pretty good engine.

But there are virtually no techs out there who will work on them. Even Freightliner shops don't like it when a bus shows up at their shop door for work.

And if you need any parts or pieces they won't be available without the added expense of shipping.

[Whitespace Lifestyle]

Originally Posted by Whitespace Lifestyle

What about 2008 Mercedes 7.2L 190HP
Any one know anything about these engines?

So We went ahead and bought this bus, we’re naming it Tyler. I spent a long time talking to a mechanic of over 30 years who has worked on bus and truck engines both Cummins and Mercedes and he said any good bus/truck mechanic will work on this engine no problem. He said he prefers the Cummins and I asked why and he said he’s old and that’s what he learned on but lately most of the engines are Mercedes up here and he likes them too. His only thing he could say as to why he prefers the Cummins was that the alternator is harder to replace (but our buses alternator has just been replaced). But he said a Diesel engine is a Diesel engine so not to worry about finding someone to work on it. Plus this bus has all its documentation on it about everything that has been done to it and they exceed any minimum manufacture recommendations. It has so many mechanical upgrades that adds value to this bus and as long as the fluids are checked regularly then all should be good and get a lot of good use out of it. Plus it’s only 10 years old.

[cadillackid]

Originally Posted by Whitespace Lifestyle

So We went ahead and bought this bus, we’re naming it Tyler. I spent a long time talking to a mechanic of over 30 years who has worked on bus and truck engines both Cummins and Mercedes and he said any good bus/truck mechanic will work on this engine no problem. He said he prefers the Cummins and I asked why and he said he’s old and that’s what he learned on but lately most of the engines are Mercedes up here and he likes them too. His only thing he could say as to why he prefers the Cummins was that the alternator is harder to replace (but our buses alternator has just been replaced). But he said a Diesel engine is a Diesel engine so not to worry about finding someone to work on it. Plus this bus has all its documentation on it about everything that has been done to it and they exceed any minimum manufacture recommendations. It has so many mechanical upgrades that adds value to this bus and as long as the fluids are checked regularly then all should be good and get a lot of good use out of it. Plus it’s only 10 years old.

Congrats on your new rig!!! and welcome to the jungle !!!!