| Author | Message | ||
| Alan Lindsey (Arl)
Registered Member Username: Arl Post Number: 2 Registered: 6-2009 Posted From: 166.216.128.153 Rating: N/A |
Howdy everyone. I've posted this on the Detroit Diesel Yahoo group and this forum was referenced there. Looks like someone here might know about our issue. We're a family bluegrass gospel music group touring quite a bit and driving tens of thousands of miles all over the US. The bus is great but I'm the only one that can drive it because of the powertrain setup. We're looking to switch out engine/tranny on our MC-9 coach from an 8v71 and Fuller 5-spd manual to something with better fuel efficiency (preferably four stroke) and an automatic tranny. Does anyone have any counsel on what engine, what transmission, and/or HOW to go about the process? Which engine/tranny combos will fit? What are the gotchas? Etc. I'm overwhelmed thinking about the various connections and systems that will need to be adapted from the existing setup to a new one. Thanks in advance for any help or comments. | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1653 Registered: 12-2000 Posted From: 76.68.135.247  Rating: N/A |
By better fuel economy, what are you hoping to achieve? You haven't got that much higher to go without changing the differential gearing too. You can burn a lot of fuel before you'll break even, unless there is drive train work required anyway. Don't be fooled! If they won't drive it with a 5 speed, don't think they'll drive it with an automatic either. It's just a handy excuse, they'll find new ones, or the truth, AFTER you spend all that ca$h. I'd be inclined to move up to a 4 stroke coach equipped from the factory than fool with a perfectly good coach. Check what the first of the DD 60 Series and Allison B500 are going for at the bus brokers. You might be pleasantly surprised in the comparison, and get a wider, possibly longer, newer coach. happy coaching! buswarrior | ||
| Don Fairchild (Don_fairchild)
Registered Member Username: Don_fairchild Post Number: 29 Registered: 3-2007 Posted From: 66.17.9.74 Rating: N/A |
Alan; The easiest thing to do is rebuild and turbo your 8V71 and add an HT740. You will need to go to bigger rad's and the bigger squirrel cage. If you go with an 8V92 you will also have to up grade the cooling system. I think there is a 740 in the classified's now. Hope this helps Don | ||
| Ron Walker (Prevost82)
Registered Member Username: Prevost82 Post Number: 389 Registered: 11-2003 Posted From: 66.82.162.10  Rating: N/A |
Cummins M11 with a B500 tranny or a 10 speed auto-shift | ||
| John and Barb Tesser (Bigrigger)
Registered Member Username: Bigrigger Post Number: 215 Registered: 9-2007 Posted From: 96.42.7.186  Rating: N/A |
Welcome to the board Alan. Bunch of nice folks here with tons of info. You have a web site for your band? We play Gospel bluegrass out of Wisconsin. As far as the repower goes, I think what BW said is right on the money. Your not going to gain much in fuel economy, so I would try to get an automatic on your DD. Anything you gain changing to a four stroke, you will probably lose on the manual vs automatic I would think, however there are a lot smarter people on here than me. | ||
| Ralph Peters (Ralph7)
Registered Member Username: Ralph7 Post Number: 28 Registered: 3-2004 Posted From: 206.251.14.87 Rating: N/A |
Run the numbers you will save about 800-900 gallons of fuel with a 2 MPG increase, running 15,000 mi. a year. I looked at going 4 cycle, even at the cheap 4 years ago my coast about 10-14K, but today an M-11 is very reasonsble, but BW has the best idea. Switch from stick to auto, lowers MPG., but easy on the leg in stop'n go traffic. | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1579 Registered: 12-2000 Posted From: 98.192.173.82  Rating: N/A |
Alan - Buswarrior is right on the money. Market's really depressed right now, good deals can be had with some homework. Your MC-9 currently gets about 6.5 mpg? Spending around $15K to install a four-stroke & automatic will yield you about 7 - 8 mpg, maybe. Those you hear saying they're getting 10 mpg are in smaller, lighter, 6-71 powered 4104s, usually. Those that say they're getting 11, well, they come up with that figure the same way the government comes up with its numbers: fuzzy math. In this case, 5 mpg in town and 6 mpg on the highway equals 11 mpg overall. It's hard to beat the 5 - 7 mpg MCI average mileage in a vehicle that has the aerodynamics of a brick. FWIW & HTH. . .  | ||
| Larry Baird (Airhog)
Registered Member Username: Airhog Post Number: 165 Registered: 1-2001 Posted From: 70.213.42.129  Rating: N/A |
I had the same setup as you but a 4 speed and switch to an 8V71T and RTO 10 speed. With 11R-24.5's I can run with the big dogs on flat land and picked up 10 to 15 mph on a 6% grade. At 33,000 lbs if I run the speed limit here in CA I can get an easy 7 mpg. I have a new 740 with retarder if your looking but like the RTO and only use the clutch to start. | ||
| Mel La Plante (Mel_4104)
Registered Member Username: Mel_4104 Post Number: 130 Registered: 7-2006 Posted From: 99.199.168.111 Rating: N/A |
Allan, you are being fooled , the other members of you group are just using you, if they can drive a car or pick-up truck the they can learn to drive the bus,you did why not them. changing out to the auto can be very expensive both in awitching cost , maintance and if you have to rebuild it it will cost more than your bus is worth. | ||
| Matt Chrisitan (Mattc)
Registered Member Username: Mattc Post Number: 2 Registered: 2-2009 Posted From: 166.183.38.9 Rating: N/A |
Isn't anyone out there doing the road-ranger bit? I had originally planned on an Eagle with 5 spd, thought the road-ranger would be a kick in the arse! | ||
| Kent Widdison (Kwidd)
Registered Member Username: Kwidd Post Number: 7 Registered: 7-2006 Posted From: 67.137.2.3 Rating: N/A |
I just got back from a 1500 mile trip in our prevost.It has been repowered with a cummins m11 and allison 5 spd auto. Milage ranged from a low of 8.8 to a high of 12 mpg. And yes I do know how to figure milage. | ||
| Larry Baird (Airhog)
Registered Member Username: Airhog Post Number: 167 Registered: 1-2001 Posted From: 75.217.66.232 Rating: N/A |
RTO = Road-ranger with overdrive, I like it. |