Newbie needs help

[Bob W]

Well I just joined another club and am looking forward to making a decision on a bus. Seems like there is a lot of nice looking buses out there. Anyone have any knowledge of the 94 Liberty 40' that Florida coach has listed. When was the switch to the series 60 made and what major differences are there between the 8V92 and the 60? Thanks all for your help.
Bob W

[Ray Davis]

Welcome Bob,

If you do a search in the forums here, you'll find a lot of discussions on Series 60 vs 8v92 engines. I would put into the seach widget terms like 8v92, s60 series 60 etc, and you'll get quite a lot to read.

A quick synopsis:

1. The change over came in early '95, I believe.
2. There were some concerns with the early S60 engines with wrist pins snapping.
3. A S60 will generally get you about 2-3 more MPG, which is significant when you're down in the 5.5 region.
4. The S60 feels a little snappier to me, off of a dead start
5. The 8V sounds MUCH better!
6. It's getting a little harder to find shops with techs that are trained in the 8V engines. Not impossible by any means, just a bit harder.
7. I think most (not all by any means) people are moving now to S60 coaches, so there are some real deals out there on 8V's.

Ray

[Jon Wehrenberg]

Welcome to the asylum. Now we have more fresh meat to play with. Especially when it is a guy like you, Bob that thinks any advice we gove you is correct.

We make up all our answers.


As to the 40 foot Liberty, post a link if you can. That way we can get specific and if you are truly lucky you may actually have a POG member as a previous owner.

In general terms the 8V92 was replaced by the S60 in the 40 foot coaches after the 45 foot coaches had been out a while. Prevost had to have the availability of the "world transmission" or the six speed as it is described in order to get the longer S60 to fit in the 40 foot shell. I think the original 40 footers with the S60 were 95 models.

There was a period when some S60 motors failed catastrophically due to separation of the piston at the wrist pin as Ray describes. If the engines made it to 200,000 miles (I think) they did not have the defective parts.

Mileage is much improved in the S60, with an average 8V92 getting between 5 and 6 mpg, and the S60 getting between 7 and 8. I get about 21 mpg on my S60 but I drive at 62.5 mph to achieve that.

If this is to be your first Prevost here is some free advice beyond posting links so we can see the coach you are considering. Decide what you really want in a coach. You can spend a small fortune trading up once you realize there are things you need. For example, in exact order there are several things we require for a coach. We want over the road air (OTR), a private toilet, and long range tanks. Somewhere down on our list of things we want, but not deal breakers are a rear closet carousel, a dinette booth and a sofa and two chairs in the living room. Our coach does not have all we want, but it has enough of what we want to be a "keeper".

Ask your questions here and let the debate rage.

[truk4u]

Bob,

Welcome aboard, you've come to the right place for information and I hope you have a sense of humor!

As you can see, I have a 94 Liberty and I had two previous series 60 buses, a 97 Marathon and 00 CC. I decided to move back to a 40' and I like the 8V's so I bought from another POG member. My mileage went from about 7.5 in the series 60 to 6.5 in the Liberty, so the additional fuel consumption was not an issue. Besides, if you buy a bus and your concerned about fuel expense, you should be looking at a Winnebago.

I wouldn't let a series 60 vs the 8V be a deciding factor. Find the bus you like at the price you want and go for it. Just make sure you are well informed and this forum will help you with all the pre-buy steps you should take. I don't know anything about the Liberty in FL, but someone here might have info on it.

[tdelorme]

Bob. welcome to POG. If you buy a Prevost, this will be the best hundred bucks you will ever spend. The Liberty on Florida Coach's web site is a nice looking unit that I personally know nothing about. I don't understand why they (Florida Coach and others) spend the dollars placing an ad and don't give us even a little bit of information about a coach. I have an older Liberty with an 8V92. The engine takes a little time to get used to if you have been driving a Cummins or Cat. Now that I have driven my bus for a couple of years, I really do enjoy the 8V. No matter which engine is in the bus you buy, spend the money to have the computer codes read. Don't buy a unit without the information available to you from the Detroit computer. And, if the computer has been reset at some point in time, find out why. Remember that any 8V is an older engine and there are a few things to check. The turbo tubes on these engines are subject to failure at some point in time. The left side (looking from the rear of the bus) is a $500 part. Look closely at the connection to the turbo and see if there are any cracks. I would even grab hold of the tube and shake it while looking. If money is not a factor, buy a 1996 or newer unit with a Series 60. My 8V get 5.5 MPG, uses almost no oil and has no leaks. These engines can be kept leak free, no matter what some salesman tells you about "they all leak." You don't say where you live, but I have a guy in Dallas that is a Detroit guru and loves working on 8V's. Take your time looking, it's half the fun and there are some great buys out there presently.

[adamdegraff]

Bob,
I am no expert on the subject, but I have heard (from experts) that some early 60's were paired with 5 speed transmissions... and they didn't work well together. I looked at a Marathon with an early 60 and 5 speed transmission. The bus was beautiful but the engine had just thrown a rod and needed to be rebuilt. It had less than 100K miles on it! Because I use my bus for work, I felt like I needed a 60 and, after hearing about trouble with the 5 speeds, I only looked for ones paired with the 6 speed Allison. Glad I did.

I like Jon's idea about making a list. I did the same thing and it ended up working out well for me. Though now, my kids are lobbying heavily for a coach with bunks for our next tour. So we are starting to consider our options. My biggest issue is that now that I have "learned" our coach, and have everything fixed up just right, I'm really hesitant to sell and buy a new one. Who are these people that I live with anyway! :-)

Good luck,

Adam

[Jon Wehrenberg]

The 5 speed transmissions were only mated to the series 60 in the early 45 foot coaches. The longer 5 speed would not work in the 40 footers hence the delay in installing the S 60 in 40 footers.

The 5 speed is actually a very good transmission and very robust and I think Peter V has the S60 and 5 speed combination. If he is not inserting moles into Brian's lawn maybe he will comment on the combination.

[dalej]

I think the 6 speed would be a plus. I wished I had a 8 speed in mine. While rolling at 2000 rpm, I'm running 67 mph. When I start to pull a hill, I wait until my rpm gauge hits 1500 then I shift to 4th. Then pull the hill until I see 2100 rpm's then shift back to 5th. It would be nice to shift at a 2000-2500 rpm drop.


Noted, I have always liked manual transmissions.

[Jon Wehrenberg]

The six speed will not give the performance of the 5 speed unless you shifted manually.

In economy mode which is the default on my coach it will not downshift until all hope of accelerating uphill is lost on the six speed.

In performance mode it will downshift sooner, and upshift later, but unlike the 5 speed it will not hang in gear as long as the 5 speed did unless you are manually controlling the gear you are in.

The five speed responded to your foot. Keep the accelerator planted on the floor and the 5 speed would hang right in gear until it hit max revs of 2150 and it would downshift if it would not over rev the engine if you mashed the throttle. Shifts were not as smooth, but neither are they on the 6 speed in performance mode.

[Scott T]

To the Vetrans of Prevost Ownership. My name is Scott Truss -Scott T and I am seriuosly looking at the 99 Marathon XLV 45, that Parliment Coach has listed. They did a PDI for me and of course there are several items (21)that need fixing or replacing- tires, batteries, bulbs, shocks, door struts, fluids changed, fuel filters changed. This is standard stuff for me, But the Sat system needs an up grade, as well as the receivers. Am I getting into a jungle? Or is this something that most coaches get in upgrades? ALSO-There is an air leak in the coach some where, not sure if it is bus side or convertor side. Anyone experienced chasing an air leak. Could this be a gremlin- like a cabinet screw into the air line for the pocket door? Any comments about Parliment service? As mentioned in a previous reply-"be ready for some surprises when getting these coaches serviced". I am prepared to a point, BUT when they quote 20 hours to complete the work, and chasing an air leak turns into an additonal 20 hours, I am not prepared to go there. I await your input.
Scott T " Just a Rookie"