Think'n of Buy'n a Big Pusher - ?? Check it out How ??

To me a big issue would be the Allison transmission. You need to take that critter on a 30 mile test run, up and down hills then travel a few miles in stop & go crawl. Look for delayed or hard shifts or ranging on grades where the transmission is having problems making up its mind which gear to be in.

I would have someone following looking for blue smoke any qty or blooms of black smoke when climbing hills and the Allison is ranging. Underneath look for fluid or fuel leaks. Check waterpump for leaks. Air brake time leakdown test then a 2nd time leakdown test with brakes applied. I own a bus with a 400 hp 855 Cummins. Hope this helps

Hi Mexicowanderer, I had a hard down shift issue with my Allison (.MD 3060 ). And the fix was sloppy throttle linkage at the engine. My rig is 20 years old and with a little adjustment with the trans cable and throttle it shifts like new still.
As you say run it around for a while and have a pro look it over, check for all the repairs, receipts and upgrades and go with your gut feeling about the seller. I am sure there will be more posts with help.

I have a 1993 HR Navigator with the mechanical 8.3 cubic inch 300 Hp Cummins and the 3060 Allison. The combination is bullet proof if it is properly maintained. We've only had one problem in the 12 years we've owned the coach, and that's when the computer control (which is under the touch pad) went bad about three years ago. The replacement was about $1,000. I've replaced all the transmission relays (in the black 6X6 box) with new relays just as a preventive measure. The relays were the same as all the others in my coach and I bought 24 in a box for about a $1 each on e-bay several years ago, so I had extras. I replace the transmission fluid about every 50K miles.

The Monaco you described has the 400 ISL, a slightly larger engine but just as reliable as the ISC, the newer version of my mechanical version. The Allison 3000 series (probably you'll have the 3060 which has an overdrive 6th gear) is the transmission of choice on almost all motorhomes and many, many medium duty trucks.

You'll love your Monaco. Since you do much of your own maintenance, it should last you as long as you'll want.

You make me feel better about "rowing" my 10/5/13 Fuller transmission. It is not the easiest thing to do in bumper to bumper traffic. But I avoid that down here. Quicksilver also has a 2-4-6 Jacobs Brake which is a very handy option. Installed a 10" "Sewerpipe" exhaust, Horton thermo-fan, and a huge Donaldson airfilter. I don't think I'm ready for computer gizmos like a keypad. For me, double-clutching is still in vogue. Whoops reminds me I need to adjust the clutch brake. Like just about everything else choices involve compromises. I am not sure that some Allison dealers do not go out of their way looking for work. And finally a good water separator fuel filter is a must
I chose a RaCor with the S series 1 micron element. Dirty fuel causes nightmares.

Suggestion: Before you buy it pull engine, coolant, and transmission fluid samples on those components and have them tested. You don't want to wind up buying a money pit!

hanzfranz60 wrote:
Suggestion: Before you buy it pull engine, coolant, and transmission fluid samples on those components and have them tested. You don't want to wind up buying a money pit!

Who are you fooling? All RV's are money pits. Period. Just how big a pit you buy.

hanzfranz60 wrote:
Suggestion: Before you buy it pull engine, coolant, and transmission fluid samples on those components and have them tested. You don't want to wind up buying a money pit!

I could do a complete fluid change before I put the coach on the market and when you pull samples, everything will be fine

A big bus? Ah come on. The owner is going to change oil. An Allison with problems will have its fluid changed probably twice trying to cure the problem.

Note: Big diesels can develop coolant leaks. One is called a "cold leak" when parked. The 2nd is a "hot leak". Pressure testing the cooling system can reveal a lot of problems including heads gaskets leaks. A cylinder Leakdown Test reveals compression issues.