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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Lonnie time to go on June 02, 2008, 10:37:13 PM

Title: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Lonnie time to go on June 02, 2008, 10:37:13 PM
I have no knowledge of buses please help
I have located a bus for sale it is a 1975 GMC P8M4905A#1265  This bus has underbody storage a raised deck, 8V71 DD mounted on a slant i think trans is on passenger side of motor. I hope it is a good thing it has an   auto trans  ,  motor does run well  new generator.
For a couple grand  $2000.00 would this be a good conversion.
I relize there is no such thing as cheap bills with a bus , but i dont want to spend that much money to start with.
Is this bus hard to get parts for???
Opinions on motor,trans and everything else wonderful good or bad dont matter
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Lonnie time to go on June 02, 2008, 10:45:31 PM
After reading some other post the shifter is on the passenger side of the driver seat.
it read 123 and D  appears to be no clutch  the  ###P8M4905A  1975 gmc I do believe that
would be manual trans  but the shifter and no clutch shows auto trans ?????
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: tekebird on June 02, 2008, 11:29:13 PM
2000 scares me....but....

the 4905 is an excelent bus.  parts are not hard to find at all with the exception of the rear window glass and the upper deck front facing glass, and rubber for those as well.  However it can be found.

find a copetant bus mechanic in your area and have it inspected first or someone quite familiar with the make/model.

it is quite possibly your 2000.00 find could cost you 10k to get it safe and reliable for road service before you even start on the conversion
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: tekebird on June 02, 2008, 11:30:07 PM
posting a series of photos will give us something to work with
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Tenor on June 03, 2008, 06:06:10 AM
Here is a list of things to look for in that particular model

Look at the wooden floor from inside the baggage bays - see if the torsion bars for the doors are pulling the floor out of shape.
Look around all of the windows for bondo or any other body filler.  These areas were made of steel and are prone to rust out.
Look at the electrical panel next to the driver's seat under the side window - you have to remove screws and check the conditon of the floor and wiring.  If that window leaks, the wiring can go bad (especially if it is cloth) and the floor can go bad.

Where is the muffler on this bus?  Is it in the engine bay between the engine and the radiator, or is it between the frame rails forward of the rear axle?  If it is under the floor, is the muffler solid?  You need to have the bus properly blocked up to safely get underneath to check.  Unless you have access to a pit, the muffler under the floor is very hard to remove and is very expensive.  It also can cause the bus to catch on fire if it is bad.  That happened to me.  Totaled my bus.  The engine bay muffler can be also very expensive, but there are other options than replacing it with an original if it is back there. 

Automatic is a good thing!  Clutch linkage can be very hard to operate on 4905's if they are badly worn or out of alignment and they don't have an air assist.

Does this model have a set of tag wheels in the last bay or is there a large section of steel frame in the rear bay?  Some models had the tags, and some just had a complete 3rd bay.

Good luck and please send pictures!

Glenn
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: roadrunnertex on June 03, 2008, 06:17:47 AM
1975 GMC P8M4905A#1265
From GMC to Stanley Cupp (Valley Coach Lines Co.) Fleet number 532 (Clio,MI)
12/1975
I own a 1974 P8M4905A and it's a good bus I have had a retired bus driver who has driven GMC Buffalo's that the GMC are a better driving bus than some of the later MCI models.
Tikibird (Derf) said so it got to be the truth!
Check for rust and condition of the coach like the previous above post lots of good tips.
From the man who owned one.
JLV
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: tekebird on June 03, 2008, 03:21:26 PM
I agree with Derf, the MC-9 are rolley poley leaners.  My 8 is noce and stable as is the A3 I presently have.

Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Lonnie time to go on June 03, 2008, 03:27:16 PM
I have tried many times to post pic error is takes to long or pic to big ????
Other info i have is the bus is flat of top no hump 6ft in
has air and someone installed auto trans ,  354.000 mile on 8v71 DD
tag axel is there kind of it look like the axel does not go all the way through the
bus.  I have heard you should remove the axel to put tanks there???
Is there any way to improve MPG in the 8v71 without tons of money also lots of oil
in engine compartment I guess its normal but would like to stop leaking. this bus does run
good but i'll still have a tech look at it.
many thanks for all the info.
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: FloridaCliff on June 03, 2008, 03:29:00 PM
Good advice by Tekebird, Tenor and JLV.

As an owner of a 4905 those are all the areas I have dealt with or would check.

Better to spend a little money for an inspection than be sorry later.

Oh and the answer to your Question/Subject: Re: IS THE BEST BUS A GMC P8M4905A

The answer is YES!

Cliff
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Ncbob on June 04, 2008, 04:33:00 AM
Oh Clifford, you've done it again. This time you've offended all the owners of those 4104's and 4106's. Not to mention Jack, Kyle and Pat and their Sceni-Cruisers.

We one the MCI side of the equation are used to your blather and pay no attention to it but when you snipe at the BusNuts in your own corral it becomes blatantly clear that you are certifiable. ;)

Bob
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Dreamscape on June 04, 2008, 04:45:59 AM
Quote from: FloridaCliff on June 03, 2008, 03:29:00 PM

Oh and the answer to your Question/Subject: Re: IS THE BEST BUS A GMC P8M4905A

The answer is YES!

Cliff

No comment!  ;D

Seriously, almost any bus is better than NO BUS!

Happy Trails,

Paul
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: superpickle on June 04, 2008, 05:58:03 AM
"354.000 miles on 8v71 DD" ...   :o

Sounds like a LOT of miles, like in " NEW Engine" soon...?
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Tom Y on June 04, 2008, 09:47:57 AM
Timetogo40, Do you know the difference between a V drive and a T drive? With the engine across the back this is a V drive. I am glad now I did not buy one. This is a personal preference, not tring to offend the GM group. The best thing to do is ask questions here, like you are doing. The pic thing on this board is a pain. Good luck.  Tom Y
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: tekebird on June 04, 2008, 09:51:51 AM
Positive points to the V drive.

makes it extremely easy to service engine, No clinbing into little holes

complete engine trans package easily taken out in comparison to T drive

Negatives, Engine spins oposite of a T drive making repowers to Cummins or Other non DD brand an issue



Additional good things about the 4905.  Largest Baggage space underfloor of any US coach until the Prevost H model and newer coaches
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: roadrunnertex on June 04, 2008, 10:08:55 AM
In reference to a "T" drive & a "V" drive engine set up.
I recall many years ago when MCI/Greyhound came out with the MC-5A and the other carriers were running the old GMC "V" drives the mechanics at Greyhound and other carriers hated the "T" drive set up because every thing was very hard to get to for maintenance air compressor,power steering, and in some cases the 50DN alternator.
A lot of carriers stayed with GMC until the end of it's intercity coach production.
I am a GMC Buffalo owner and it's a wonderful machine.
I am not trying to say the other intercity coaches are a bad product.
But I will keep my old Buffalo thank you.
jlv ;D
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: tekebird on June 04, 2008, 12:47:56 PM
Today Still there are Owners and maint supervisors who say that if HM started producing v drive buses they would buy them solely from an ease of amint perspective
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: 4905 doc on June 04, 2008, 02:13:15 PM
IS THE BEST BUS A GMC P8M4905A ?     
   Yup.
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Lonnie time to go on June 04, 2008, 03:40:40 PM
I dont know how to thank everybody for there info.  I will say its great good or bad I  want to here it.
The guy who owns the bus is retired diesel tech from the army.  I will have the bus checked out by another diesel tech before i get it. v-drive sounds good and bad like other drives Very little rust on bus
to worry about   But i am wondering about the tag axel, dont know if i should take it out to use the bay for other stuff or leave it in.
As far as to improve MPG hoping to get 10mpg  Yes I am dreaming big
I will add that I would not even think of getting a bus if not for the help and info from the great people on this site , so thank you again.
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: tekebird on June 04, 2008, 03:51:58 PM
Take the tag axle out....you won;t need it and it is just anohter set of tires bearings bushings etc to worry about.

you WILL NOT GET 10mpg......figure on 6 and 7 on a good day...if your engine is tires or you have a heavy foot maybe as low as 4.5

you Should get a Bus mechanic to look at it, not a General Diesel Tech.

When you get it find yourself a bus mechanic to do work yoou don;t want to do.  Not a truck mechanic.

Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: kyle4501 on June 04, 2008, 03:58:27 PM
If it ain't the best, it is only because of the 4501  ;D


You'd only need the tag for weight carrying capacity. Are you planning on carring all that weight? Most don't, so removing the tag would probably be a good move for you.


BTW, My last 4501 purchase got almost 10 mpg on the 600+ mile trip home & our T.O.A.D. was a ford ranger  ;D
8V71 with a greyhound rebuild tag & a 4 spd. Didn't use much oil either  ;D
Title: Re: IS THE BEST BUS A GMC P8M4905A HELP PLEASE
Post by: Barn Owl on June 06, 2008, 10:54:56 PM
A GM is a very well engineered bus and in many ways was ahead of it's time. If they weren't so expensive to build and update they might still be around. As others have said, it is one of the easier buses to work on and parts are inexpensive and easy to come by. It is also one of the least expensive buses to purchase. Because of that they can be a problem if you ever decided to sell it. You will take three or four times the burn that you would if you did the same with a MCI or a Prevost. They cost little or nothing up front, and you get little or nothing for them in the end, but it cost the same to convert as the others. This topic has been discussed a couple of times so you might want to search this BBS for some past posts. BTW I am a big GM fan, but they are what they are.