9.5 x 16.5 ties on my 75 Glenbrook

T

terry1

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My new coach came with 9.5 instead of the recommended 8.75 x 16.5 tires they are all in decent shape except one front tire that needs to be replaced I
am thinking of replacing both front tires with 8.75 and leaving the back for now. I would like to get the aluminum wheels but I only have so much to
spend and I want to be sure I have no major mechanical issues before I get to things like new rims. I am wondering if mixing the sizes would be a
problem or if I should just buy one new 9.5 for now. Any suggestions
--
Terry
75 Glenbrook
Dauphin, Manitoba
 
> My new coach came with 9.5 instead of the recommended 8.75 x 16.5 tires they are all in decent shape except one front tire that needs to be
> replaced I am thinking of replacing both front tires with 8.75 and leaving the back for now. I would like to get the aluminum wheels but I only have
> so much to spend and I want to be sure I have no major mechanical issues before I get to things like new rims. I am wondering if mixing the sizes
> would be a problem or if I should just buy one new 9.5 for now. Any suggestions
Mixing sizes side to side on the front would be a problem (would ruin the final drive). Mixing sizes on one or two of the rears might mean you would
have to set ride height manually to keep the frame the right distance from the ground to not mess up steering/handling. It might not be wonky enough
to matter, but if it is, you will know it.

Your spare will need to be the same as the front. Since you have a different size on the front than the rear, if you have a flat on the rear, you
will have to set ride height manually until you get someplace where you can get the tire situation sorted back out.

A hassle, but manageable.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
As long as you have both tires on the front the same size it should be OK.

Not as critical on the back as they are not connected.

Emery Stora
77 Kingsley
Frederick, CO

>
> My new coach came with 9.5 instead of the recommended 8.75 x 16.5 tires they are all in decent shape except one front tire that needs to be replaced I
> am thinking of replacing both front tires with 8.75 and leaving the back for now. I would like to get the aluminum wheels but I only have so much to
> spend and I want to be sure I have no major mechanical issues before I get to things like new rims. I am wondering if mixing the sizes would be a
> problem or if I should just buy one new 9.5 for now. Any suggestions
> --
> Terry
> 75 Glenbrook
> Dauphin, Manitoba
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Terry
Check with Mackie? Love in your area. He may have left over GMC stuff,
possibly 16" steel wheels . You don't know unless you check.
The last time I was in Dauphin his was parked by his house but I believe
he has sold since then.

Mike in NS

> As long as you have both tires on the front the same size it should be OK.
>
> Not as critical on the back as they are not connected.
>
> Emery Stora
> 77 Kingsley
> Frederick, CO

> >
> > My new coach came with 9.5 instead of the recommended 8.75 x 16.5 tires
> they are all in decent shape except one front tire that needs to be
> replaced I
> > am thinking of replacing both front tires with 8.75 and leaving the back
> for now. I would like to get the aluminum wheels but I only have so much to
> > spend and I want to be sure I have no major mechanical issues before I
> get to things like new rims. I am wondering if mixing the sizes would be a
> > problem or if I should just buy one new 9.5 for now. Any suggestions
> > --
> > Terry
> > 75 Glenbrook
> > Dauphin, Manitoba
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS

Life is too short to hold a grudge; slash some tires and call it even !
 
> My new coach came with 9.5 instead of the recommended 8.75 x 16.5 tires they are all in decent shape except one front tire that needs to be
> replaced I am thinking of replacing both front tires with 8.75 and leaving the back for now. I would like to get the aluminum wheels but I only have
> so much to spend and I want to be sure I have no major mechanical issues before I get to things like new rims. I am wondering if mixing the sizes
> would be a problem or if I should just buy one new 9.5 for now. Any suggestions

Terry,

Mixing tires on the steer (and in this case drive) wheels is a notably poor idea. If you do mix them, you can have the major mechanical issue you are
hoping to avoid. You can also have some really strange handling issues. If you have a spare 16.5 rim, you could shoe that with a 8.75 for a set and
carry the 9.50 as a spare. You can also buy the set of alloy 16.0 and change out a pair at a time. My coach has been 3 years waiting to have all
the wheels match. The spare is still a 16.5.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Thanks for input I will try and contact Mickie he is not listed in new list but will track him down thru mutual friends. Are you mixing 16 in rims
with 16.5 ?
--
Terry
75 Glenbrook
Dauphin, Manitoba
 
Thanks are you mixing rim sizes ? 16 on front and 16.5 on back ?
--
Terry
75 Glenbrook
Dauphin, Manitoba
 
Terry,

I am remiss. I only just now noticed that you are new here.

Welcome to the group, family, cult, asylum...

As you have already discovered, this is a community like few others. These are wonderful helping and very supportive people. It is a really great
place to be. And when you get to a rally, you will also find that you have acquired a large collection of brand new old friends. The only other
community that I know of that is at all like this is that of the watermen that are my world. For that reason, I have taken to welcoming new owners
here much as any new owner or vessel would be welcomed there. So,

May the Good Lord bless this coach and all those that set forth within here.

Welcome Terry

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
> Thanks are you mixing rim sizes ? 16 on front and 16.5 on back ?

Terry,

I was indeed. At one time I had 225-16 on the front and all 8.75-16.5 on the rear. Then, I had the 16s on the front and middle and 16.5 on the rear.
And for a short drive (200 miles), the rear was a 3:1 mix because the spare was/is a 8.75-16.5.

There were no handling issues.

Matt

--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
> Terry,
> I was indeed. At one time I had 225-16 on the front and all 8.75-16.5 on the rear. Then, I had the 16s on the front and middle and 16.5 on the
> rear. And for a short drive (200 miles), the rear was a 3:1 mix because the spare was/is a 8.75-16.5.
>
> There were no handling issues.
>
> Matt
You weren't actually driving with different size wheels. The difference in diameter between 8.75R16.5 tires and 225/75R16 tire is negligible.

The difference between 9.5R16.5 and 8.75R16.5 tires is NOT negligible (at least side-to-side on the front/drive axles).

Terry,

Matt could have probably gotten away with mixing side-to-side, even on the front. You will muck up the final drive if you do that with one 9.5R16.5
wheel on one side of the front and either an 8.76R16.5 or a 225/75R16 wheel on the other front wheel.

Mixing side-to-side, or mid and rear, on the back may or may not be noticeable in the handling, but you won't muck up the final drive.

I would guess as long as you have the same size on each side-to-side pair, you will be fine. You might even get away with one odd size different than
the other three on the rear.

DO NOT mix sizes from one side to the other on the front.

Your spare should be the same size you run on the front, in case you get a flat on the front.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
I concur much impressed by great folks here looking forward to many years of friendship and enjoying our gmcs
--
Terry
75 Glenbrook
Dauphin, Manitoba
 
Thanks for input it looks like my best option short term is too buy two new 8.75 s for the front but may spring for two new rims have too see how my
bank acc holds up. I actually have a total of 9 16.5 rims from PO.
 
I am hoping you have already included the tire age in your assesment of them looking "decent". The problem for our coaches is if they blow, the debris
(especially if still attached and spinning) tears off much more body work than the cost of tires. Much has been written on this forum about tires
aging out before wearing out. Five years is the preferred replacement age, each year past that has fewer advocates. I just bought a coach with seven
BFGoodrich tires, three dated 2006, four dated 2011. It is killing me to scrap tires that have less than a few hundred known miles on them. The 2006's
will definitely not be put on the road, the 11's will probably be used to get it home. The date codes are at the end of the DOT sequence on the
sidewall. If it says 2312, that is the 23rd week of 2012. Older tires do not always have four numbers, using a single digit for year.
--
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
 
To 'splian the problem, unequal diameter wheels/tires side to side means the whels turn at different speeds. On the back on a GMC it doesn't matter,
because there's no connection from side to side. In front, you'll turn the axles at different speeds which will make the differential behave is
though the coach is in a turn. It isn't designed to do this for any great length of time, or at any great speed. If you have a limited slip or
'locker' differential, you'll get it real hot real quick and it will fail shortly thereafter due to the unequal axle speeds. I carry two spares in
the ratrod truck, the front and rears are different diameters so comes a flat I replace each side with identical spares.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"The road goes on forever, and the party never ends" --Robert Earl Keen
 
Checked with PO tires are past 10 years but he swear they will be fine I think I will replace front two and use the rest to get it home for now. I
confess I never factored $ 3,000 for tires and rims into my budget. Good lesson for future.
--
Terry
75 Glenbrook
Dauphin, Manitoba
 
Only costs $3,000to $ 6,000 to to repair the damage caused by a blow out

On Mon, Feb 13, 2017 at 12:46 PM Johnny Bridges via Gmclist <

> To 'splian the problem, unequal diameter wheels/tires side to side means
> the whels turn at different speeds. On the back on a GMC it doesn't matter,
> because there's no connection from side to side. In front, you'll turn
> the axles at different speeds which will make the differential behave is
> though the coach is in a turn. It isn't designed to do this for any great
> length of time, or at any great speed. If you have a limited slip or
> 'locker' differential, you'll get it real hot real quick and it will fail
> shortly thereafter due to the unequal axle speeds. I carry two spares in
> the ratrod truck, the front and rears are different diameters so comes a
> flat I replace each side with identical spares.
>
> --johnny
> --
> '76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and
> add - ons.
> Braselton, Ga.
> "The road goes on forever, and the party never ends" --Robert Earl Keen
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://bdub.net/gmcmotorhome.info/
Alternator Protection Cable
http://bdub.net/gmcmotorhome.info/APC.html
 
He 'swears they're good' manufacturer says they're aged out. Who you gonna believe? Eagles from JimK, cooper Discoverer III LTs a bit under 2500
scoots all up. I only bought 6, take my chances with a steel rim for the spare.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"The road goes on forever, and the party never ends" --Robert Earl Keen
 
Not knowing what your coach needs, your budget, and how you want to use it, it is hard to advise - but that hasn't stopped us before! I bought my
first coach four summers ago. I put a full set of six Transforce 16.5 tires on it because i didn't know how much it was going to take to make the
coach a runner again, nor how much my family would use it. We do use it quite a bit, I have restored the major systems, and will aim for 16 inch
wheels and tires, two per year when I hit the five year mark on these tires. They will not be worn out.

I also have a 75 Glenbrook, and another consideration is that they had not switched to radial rated wheels by then. Ideally, you should only run the
old bias ply tires on them. Very small risk of wheel welds actually separating with radial. You can look for a stamped "R" after the wheel code inside
rim. That would indicate radial rated if the R is present. If no R, another reason to look for steel or alloy 16s. Steel 16s are available, you can
search this forum (top right of page) for part numbers on used ones.

--
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
 
Terry,

when I bought mine in San Diego I replaced all of the 16.5" tires on it.
Total cost was 1200+change. I didn't and don't see a need to change rims
as well. I see it different for a coach I am looking at to move to
Europe, as you can't get 16.5" tires in Europe (or at least nobody that
I know can find any).

--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA
 
> Terry,
> when I bought mine in San Diego I replaced all of the 16.5" tires on it.
> Total cost was 1200+change. I didn't and don't see a need to change rims as well. I see it different for a coach I am looking at to move to
> Europe, as you can't get 16.5" tires in Europe (or at least nobody that I know can find any).
>
> --
> Best regards
> Peer Oliver Schmidt
> '76a Eleganza II, VA
16.5" tires are hard to find stateside too. Not that hard on the internet, but if you need a tire in some one horse town in the middle of nowhere, you
might find yourself spending several days there while you figger out how to get a tire shipped to you.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
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