Hey guys,
We've been shopping around for our bus for the last few months. As we close in on the bus we're about to buy, I wanted to get your thoughts on a couple of things; with more to come I'm sure...
It is a GM 4107
The tires on it are a bit long in the tooth and I want to replace them. Any advice on brand, type, etc of tires? We're not looking for "million mile" tires as we'll most likely be putting only a few thousand miles on it a year. We plan on living in it fulltime; so predictable, reliable and safe are obviously high on our list. I'm willing to consider used tires if I can understand a bit more on how to buy good ones. I will probably only do used tires on the drive tires and new for the steer. Any other advice on buying tires and having them installed? If there's a particular shop you prefer, also please share (it's in the Sacramento area).
The current owners mentioned these wheel balancer things that can be installed on the tires(wheels). After talking with the owners and reading about them online, I'm very interested in having them installed on the bus. Anyone using those now? Any experience/thoughts on them? I see two brands that seem to come up, Centramatic and Balance Masters. Any preference towards one or the other? Is so, why?
While talking with the owners they'd also mentioned a safety item that can be installed on the steer axle to "assist" in case of a steer tire blowout. Although we'll be installing new tires on it, s**t does happen and the more I can increase the time window to react to something like this the better. We're pretty new to buses and driving a vehicle this large, so we're choosing to err on the side of caution. From my understanding, this device is basically a shock absorber that dampens the initial shock/adverse steering with a steer tire blowout. It sounds simple enough. I've tried to do some research online for it and have come up rather empty handed with lots of vague info. So I'm hoping some of you folks have seen these things, preferably are using them, and have some thoughts to share. One concern I have is having another thing, possibly interfering, between turning the steering wheel and actual steering. Plus I'm not sure how this thing would respond if I actually needed to make a significant steering correction (obviously in an emergency) on purpose.
As always, thanks a lot in advance for any help or advice you can share.
Thanks
George
George,
Welcome to the board!
Click the word search in the blue line above, type in tires, I think it will answer your questions.
Good Luck,
Most buses used 12R-22.5 16ply tires. But once you're converted with all your junk inside, you probably won't need the weight carrying of the 12R-22.5. Reducing to a 11R-22.5 16ply will be a much more popular tire-even though you go from 485rpm to 497rpm-which means if your turning 1800 at 65mph, you'll be turning 1845rpm with the 11R's. Get the bus weighed by axle to find out what tire you can run. Then run that tire at the tire manufactures tire pressure to get the best ride and tire wear.
I suggest using what is called a regional tire. They are usually rated to 75mph, but have a stronger side wall and with stand scrubbing-like around town driving.
Use new tires in front-always! And used tires can be mounted on the drive axles. Unless you're anticipating going off road, or doing winter driving, all position tires can be used on the drive. They will typically get better fuel mileage then traction tires.
When I drove truck, I tried all of the tire balancing methods-Equal which is a sand like stuff installed inside the tire; balance masters use mercury as the balancing. Both these don't work worth a hoot. What I found works best-when buying a tire, have it spun balanced, then run Centramatics-which is a balancing ring that mounts behind the wheel with ball bearins in automatic transmission fluid. There's enough weight in the ball bearings to make a difference.
If you have integral power steering (in the steering box-like Sheppard) you don't need any other assistance on the steer axle. You'll be surprised how fast a bus can react to a jerked steering wheel in a emergency.
Run a name brand (non Chineve)timer and you'll be fine. Good Luck, TomC
Just for our info....standard or automatic and manual or power steering?You could consider Bandag Recaps in steer tread on the back.
You don't need any type of steering assist if you have either the original hyd boost steering or a Sheppard full time PS conversion.
Manual - maybe, but the manual system is geared so low that you probably don't.
This is a very, very low bus, if you change to 11:00s it will probably be another inch lower. I would stick to 12:00s.
If you keep good rubber on the steer axle, you shouldn't have to worry about blowouts, just keep an eye on the age and weather checking
George -
Welcome aboard! Always willing to help a new busnut!
Besides what Chessie asked (stick or auto trans, manual or power steering), what size tires are on the coach now?
Also, if the coach has an automatic, which one? A VS, VH or V-730? Makes a difference.
We'll bombard you with info once you fill in the blanks, as this topic has been beaten to death over and over and over here and over on the BNO (www.busnut.com (http://www.busnut.com)) board.
And if you really want to start a firestorm, ask about oil for the Detroit 8V71!
FWIW & HTH. . .
;)
Excellent! Thanks for the great info so far guys.
Duhhh, I should've included some additional info on the steering and trans. :)
It does have (full time) power steering, I think it's a Sheppard, but I'm not certain of that.
It's also an auto trans running a V730 (with lockup if that makes much difference).
The tires on it now are 12Rx22.5 and I think I'll stick with 12s. Not that I'm going to be doing a lot of off roading in this :), but I think it's low enough to the ground that an inch will make a difference in some places. Would there be any particular advantage to 11s?
Thanks again all!
George
George -
Thanks for filling in the blanks. Now we can give you more intelligent answers!
With power steering on a coach, don't waste your $$ on a "Steer-Safe" unit. Those are designed for the S&S market. Best thing to do if you have a front blow-out is to STAY OFF THE BRAKES until you gain control, then start slowing to a stop. Run new tires on the front axle, and maintain the correct air pressure to reduce the risk. Most tire failures are from UNDER inflation, so monitor the duals, too.
This next is a little techie, so bear with:
GM designed the 35-foot coach's powertrain around tires that turned 495 revs per mile using the stock 4.125:1 rear axle ratio.
With the manual 4-spd, the bevel gear ratio is 0.808:1, which, when multiplied by the rear axle ratio of 4.125:1 gives an OVERALL rear axle ratio of 3.333:1.
With the V-730, the bevel gear ratio is 0.875:1, resulting in an OVERALL rear axle ratio of 3.609:1, approximately an 8% reduction.
Translation: Better acceleration with the automatic, but lower top speed, more engine revs per mile and greater fuel consumption. (Based on the 495 revs/mile OEM tire.)
Ideally, keep as close as possible to the 495 number when buying drive tires. If you want to recapture some of that lost percentage because of the automatic, then buy tires that turn roughly 470 revs/mile.
The only tires that I've found in the 470 range are 11R24.5s, which would mean new wheels as well on your coach. Maybe not an issue if it currently has steel wheels, but if they're aluminum, you may not want to replace them.
Your choice, but this is background info to help you make an informed decision.
FWIW & HTH. . .
;)
12R-22.5=485rpm. 11R-22.5=495rpm. 11R-24.5=476rpm.
Of these three tires, the 12R will be the hardest (and probably the most expensive) of the three. Then the next hardest is the 11R-24.5. The 11R-22.5 will be the easiest to find, although most all over the road trucks are now using low profile tires. Most buses now use the metric 315/80R-22.5 (real expensive) along with most trucks in Europe. Good Luck, TomC
George In West Sacramento there are quit a few Commercial tire dealers just across the river from Sacramento. Goodyear Heavy Truck for one.
49er Truck Plaza is another and they have a bus wash there also!...
G & S Commercial Tires and wheels, in Roseville, CA off PFE Road. ;D
Dave
So, if someone had 3:70 or 3:90 ratio gears manufactured for the GM's, there could be a fair amount of interest in getting them if the price wasn't exorbitant?
Listen to RJ.
The best thing I have done to HUGGY is to replace a set of 315 24.5 low profile with a set of 11r24.5 tires. Bought Hankook because of the price and available
and getting rid of Michelin 5 year old that I had two blowouts with. both on the inside rear.
Makes cruising down the inter-state a lot easier and the fuel mileage is noticeable better. about 12 mpg 6 going and 6 coming back makes 12 in my book.
uncle ned
4104 with 6v92 and v730 and the tall gear for a 4106 rear end.
Quote from: uncle ned on February 07, 2014, 07:27:32 AM
Makes cruising down the inter-state a lot easier and the fuel mileage is noticeable better. about 12 mpg 6 going and 6 coming back makes 12 in my book.
uncle ned
4104 with 6v92 and v730 and the tall gear for a 4106 rear end.
Like your mileage calculator, Uncle Ned. I get about 10 MPG with that math. Feel better already.
Glen S.
We have a PD-4108, very similar to your PD-4107. We bought a set of six new 12R22.5 tires. What a difference in handling! The former tires had lots of tread left but were between 7 and 10 years old and mis-matched brands.
Don't forget the spare tire. Hopefully you'll have the tool in the bus for the front bumper. It hinges downward to expose the spare tire compartment. Our spare was on an old split rim so we got rid of it and picked up a used 12R22.5 tire and rim. Watch how the old spare comes out. The replacement has to go in with the same side down.
Bryan
My 4107 also has a V730 plus Sheppard full time steering and it is a great combination.
There is no top speed problem with this bus , take my word for it. A lower gear is better for starting from a dead stop and steep hills. I've found myself wishing for a slightly lower first gear a few times. It is no speed demon at first moving but once it gets rolling you are gone. Sort of like a locomotive!!
Yeah, I know...some people are happy with 50 to 55mph cruising too.
Lots of good info, thanks!
So it sounds like I'll stay with the 12R22.5 s. I don't want to buy new wheels for it, plus I would like to stay close to the recommended rpm
It also sounds like I can skip the steer assist thing as it appears the power steering is geared such that that is not much of a concern. In any case we're going to put new tread all around and monitor them closely for wear and appropriate pressure.
As far as the balancers, I'm leaning towards the balance masters. I've read up on them and some of the reviews. They're equivalent in price to the others and the way they're described, sounds like it should work better, have been in use for a long time, and by quite a few different applications.
Thanks again!
George
I would mount the tires without balancing them. Chances are they will be smooth riding enough. If not, then take them to be balanced. I have driven lots of miles on lots of buses without balanced tires that rode just fine. The tires on my current bus are balanced, and sure it is nice and smooth, but it probably would be just as smooth without.
JC
We use the Centramatic balancers and have been happy with the results. They sometimes can be found on Ebay and Craigslist reasonably priced. The Balance Masters look to be the same but use mercury rather than steel balls.
Is there a different number for the 315/80r22.5 tires? Its about time for me to start looking for new ones. I have a 1962 Pd4106.
Ed
Seems Awful big for a 4106
Sent from my iPhone using Tapatalk
That is a big tire, almost 13", must be crowded in the wheel well? Probably way overkill for a 4106.
Weigh your bus front axle, back axle. Then see what tire you should run. A 315/80R-22.5 is both a large tire and expensive tire that I doubt you need. Something more like the 11R-22.5 would work. If you're heavy on the front, the 11R-22.5 16ply will go to 13,200 lbs. I run 11R-24.5 for biggest diameter and raise the bus up maximum. Since I only have 10,500lb in the front and 20,500lbs in the rear, I only run 90psi all around. Rides great. With a GVW rating of 13,000lb front and 23,000lb rear, I'm 5,000lbs under the chassis rating!(and the 11R-24.5 tires can take that load if inflated more) One of the many reasons I run a bus. Good Luck, TomC
Quote from: eddieboy on February 28, 2014, 01:46:43 PM
Is there a different number for the 315/80r22.5 tires?
Ed -The truck tire market is in the process of switching over to the metric sizing like the automotive market has now used for over 10 years. Confusing for awhile, until you take a few minutes to figure it out.
I notice that your sig line says you still have the manual 4-spd in your coach. Since that's the case, figuring out which tire to put on when you buy new becomes really easy: Simply remember 495 revs per mile, as that's the size GMC used when designing the powertrain gearing. With that number in mind:
Tires that turn
MORE than 495 r/m are going to lower your top speed and increase your fuel consumption.
Tires that turn
LESS than 495 r/m will have the opposite effect.
So it really doesn't matter if the size on the sidewall is "traditional" (12R22.5, 11R22.5) or "metric" (295/80R22.5, 315/80R22.5), the number you're really interested in is the revs per mile. The closer you get to that number, the closer your coach will perform to OEM specs.
Keep in mind, too, that the larger the tire, the more expensive and the greater the federal excise tax you'll have to pay.
Finally, after you coach gets it's new shoes, run it across some scales to get the weight on each axle so you can set your air pressure correctly for the weight being carried. All the manufacturers have load inflation tables to help you.
Oh, and for heaven's sakes - pay to have them BALANCED by the tire shop before you mount them on the coach! The few extra bucks, IMHO, is well worth the price. I struggle with those who claim that Centramatics or Balance Masters work as well as individual balancing, but to each their own. . .
FWIW & HTH. . .
;)
Most tires the balance is not the problem with the tires the drums are out of balance the balance masters and other brands of that type do help with correcting the problem IMO
In general the wider the tire the greater the circumference and the greater the load capacity in the same series (sidewall height) and mfg.
I think the 4106 originally had 1200 (295mm) x 20 bias tires (22.5 equivalent) but I stand to be corrected on that, they may be 1100s. I also believe most were 80 series. It is not a really heavy bus.
For our converted, lighter weight buses it makes little sense to go to heavier, more expensive tires. It even makes sense to go to smaller sizes or load ranges if circumferences can be maintained.
hi tom I replaced my 12R22.5 's with 11r's went with Michelin love them . also installed the blu-ox true center stabilizer love it if you get caught in a bad cross wind you can steer head on and set instead of fitting it love it also insurance for blow out
my bus has 4 speed and 8V71 get 10 or better all day but we don't have many mountains up here
Well that really makes me think that the PO must have made some changes. Actually one of the tires is a different size than the rest. I just went thru the manual but can't find the specs for the original tire size. If these are too big, I can maybe save some money by going to a different rim and tire. If anybody knows what I should have on the ole gal, please chime in.
Ed
Quote from: eddieboy on March 07, 2014, 06:53:18 PM
I just went thru the manual but can't find the specs for the original tire size.
Ed -The OEM stock tire size for the 4106 was
11.00x20 tube-type BIAS PLY on split rims that turned 495 revs per mile. Some Greyhound divisions back then spec'd 19" wheels/tires to reduce theft, others spec'd 22.5s - but that's ONLY Greyhound. Most other carriers simply opted for the stock size.
20" wheels & tires are almost impossible to find nowadays, everything is either 22.5" or 24.5." Ditto for tube-type tires, let alone bias-ply construction.
As I said in my earlier post above, look for tires that turn as close to 495 revs per mile as possible for OEM performance with your 4-spd manual. 22.5" or 24.5" rims, doesn't matter except that 22.5's are the most common. Just stick to the 495/mile number for best results.
FWIW & HTH. . .
;)
So if I end up changing tire size, do I need to change the rims as well or just go with a smaller sidewall???? Is this a good question for Luke or some other expert?
Ed
22.5 x 8.25 rim for tubeless tires is the most popular rim made. You can run a 10R-22.5, 11R-22.5, 12R-22.5, 255/80R-22.5, 265/75R-22.5, 275/80R-22.5, 295/75R-22.5, 295/80R-22.5 (at reduced carrying capability over a 9" wide wheel), 315/80R-22.5 (at reduced carrying capability over a 9" wide wheel. For closeness to the magical 485 rpm, which is the 12R-22.5, the 11R-22.5 is very close at 498 rpm. Good Luck, TomC
Quote from: eddieboy on March 09, 2014, 05:21:19 PM
So if I end up changing tire size, do I need to change the rims as well or just go with a smaller sidewall?
Ed -Simple answer: Maybe, maybe not.
But to answer your question more intelligently, what size wheel/tire is on your coach now, front & rear?
Quote from: eddieboy on March 09, 2014, 05:21:19 PM
Is this a good question for Luke or some other expert?
I think Luke will echo what's already been shared with you for wheels & tires, plus will supplement that with "make sure your wheel studs and lug nuts are in good condition, as well as the wheels themselves. If in doubt, replace them."
Quote from: TomC on March 09, 2014, 05:38:41 PM
For closeness to the magical 485 rpm. . .
Tom -I believe this is a typo on your part, correct? The magical number is 495 for GM coaches.
I've also noticed, when looking at tire spec charts, that often the same size tire (let's use the common 11R22.5) will have quite a range of
revs per mile among different manufactures, and even among different tire types from the same manufacturer, such as all-purpose vs steer vs drive only. So one has to really do their homework before plunking down their hard-earned cash when buying new shoes for their ride!
FWIW & HTH. . .
;)
Most 12R-22.5's that are used on buses are 485rpm tires. 11R-22.5 drive tires are around 498rpm. The only tire faster then the 12R-22.5 is the 11R-24.5 at 476rpm.
If 495rpm was the magical number, then what tire size was that? Good Luck, TomC
Quote from: TomC on March 09, 2014, 09:45:44 PM
If 495 rpm was the magical number, then what tire size was that?
10.00x20 tube-type bias ply.
This was the size that the brilliant engineer Dwight Austin used when developing the revolutionary (for it's day) V-drive for the Greyhound-only Yellow Coach 719 introduced in late 1935. Based on his 1932 patent, and originally installed in the Pickwick Nite Coach (see the Santa Fe version below), it was really the beginning of a design concept that basically is still in use today. Granted, 99.9% of North American buses are all T-drive, but Austin's original concept paved the way.
The YC-719 used a GMC 707 cu. in inline 6 gas engine, coupled to a 4-spd manual gearbox, a 4.125:1 rear axle ratio and 10.00x20 tires.
In 1937, YC introduced the 743, which was a mild face-lift of the 719, but more importantly, introduced the venerable 6-71 Detroit Diesel and coach air conditioning. No other changes were made to the drive line specs with the change to the Detroit, as the 707 operated w/in the same RPM range.
IIRC, the 12R22.5 (or it's bias-ply equivalent) size became the stock OEM installation when GM introduced the 40-foot 4903 in 1968, but am not sure. All of my 4108 and 4905 sales literature indicate 12R22.5 as the stock tire.
How's that for historical GMC coach trivia? Hehehehe. . . :D
FWIW & HTH. . .
;)
Per RJ the 476 tire in the 11r24.5 size was the best thing I did for huggy.
run down the highway easy now.
uncle ned
huggy bear
4104 with a 6v92 and v730
Is 470 to 480 RPM pretty standard for a 11R24.5 tire? The data plate for my bus shows a metric size of some sort for the tires so I have no idea what the correct RPM should be.
just look up the tire size on line. Good Luck, TomC
After looking closely at my wheels, I found that I have 3 different sizes on the bus. I called Pomps and they said any of the 3 different sizes should be ok. He recommended the 12R22.5. I think the 11R22.5 might be a less expensive alternative.
Quote from: eddieboy on March 18, 2014, 11:03:53 AM
I think the 11R22.5 might be a less expensive alternative.
Ed -Here you go: Bridgestone all-position model R250F, size 295/80R22.5, load range G (plenty for the '06) and best of all: 499 revs/mile.
How's that for almost exactly what the powertrain was designed for? (495)
The 295/80R22.5 is just a little bit taller than an 11R22.5, which, in the same tire, turns 503.
More food for thought!
FWIW & HTH. . .
;)
Straight from the Michelin Commercial Tire site-all listed are the XZE for front axle:
11R-22.5 16ply 501rpm 13,220lb
12R-22.5 16ply 486rpm 15,780lb
275/80R-22.5 16ply 517rpm 14,320lb
295/80R-22.5 16ply 500rpm 14,600lb
315/80R-22.5 20ply 489rpm 18,000lb
Weigh your bus. Unless you are more than 13,000lb on the front, I'd stick with 11R-22.5. Easy to get on the road and used quite a bit. 275 is the most popular size (crosses also with 295/75). Good Luck, TomC