275-70 FOR TAGS ON MCI'S???

[trailblazer2]

 Anybody out thar using,or thought of using a smaller size tire on thu tag axle? The MCI 6 was designed this way;I beleive? Anyhow these ole tags don't carry the weight on conversions/as oppossed to the commercial coach do they? There are lots of 1100's out there, the cost ,and the availablity is a ******
factor too! My opinion is there would be less friction(especially in the tight turns?) Let me know the pros,cons, and absolutes!
Bill

[Jerry32]

With the reduced wieght of a conversion you could probably goe with 1100 's all around . Jerry

[Hartley]

Tags are matched to drive axle brake drum ratio. Putting a smaller tire on will probably cause the tags to lock up and skid.

I know that even having not enough tag pressure makes them skittish ( skiddish ) and having the right downforce and the correct tire diameter that matches is important unless you change the amount of pressure applied to the tag axle brakes. And the correct amount of downforce loading on the tag axle itself to limit skidding.

Tags take a lot of sidewall abuse in tight turns also. Are you sure that you want to mess with the overall handling of the whole coach by messing with mixed tire sizes.

If you want to have some fun. Try turning off the air to the tags and drive down the highway and see what effect that can make.

It's not fun when the front tries to wander across the crown of the road unexpectedly. That downforce on the back end stabilizes the front end considerably. I found out when my regulator for the tags got out of whack.... Took both hands on the wheel, but with the right pressure and tracking it only takes 2 fingers to keep it on the road where you point the nose.

The Old MC6 was specially equipped with giant drive tires and a brake-compensated tag axle system. That could have been why only 101 were ever built. Too hard to maintain due to non-interchangeable parts and tires (huh?)....

I went with 315-80/R22.5 all the way around my MC9 and plan to keep it that way. that's what the factory installed and that 9 inch wide tread provides a lot of float and traction that is predictable. My goodyears cost me about $701.00 each mounted and balanced with a 7 year warranty... I only wanted to buy tires once.....

Good Luck....

[TomC]

You could go with 11R-22.5 16 ply.  They still have strong sidewalls, but are cheaper than the 12R.  I wouldn't advise the 275/70.  This is a low profile tire mainly made for height sensitive vehicles like car carriers.  The height difference may make the brakes skid or the suspension hyper extend possibly breaking a shock or blowing the air bag. 

$701.00 each mounted and balanced, especially for Goodyears is pretty steep.  A year and a half ago I had new Michelin XZE 11R-24.5 16ply mounted and balanced with new stems for $485.00 apiece-and I thought that was high!  Good Luck, TomC

[TomC]

PS- this last week I talked to my tire guy about 315/80R-22.5 for a friends truck that was heavy on the front.  Michelin XZA2's would have been $550.00 each mounted and balanced.
Everyone-beware of being overcharged just because you have a bus!  Good Luck, TomC

[Hartley]

I probably should have said what I bought...Hmmm...

G670RV Goodyears, They are a 7 year tire vesus a 2 year tire that most other manufacturers build.

Taxes and fees along with higher than usual dealer charges ran the price up. The tires were $ 586 each
before FET, FL Sales, Disposal, Gross Receipts and some other tax. Then the dealer charges for mounting
and balancing.

The size of the tire also makes the price go up. as there are only a few manufacturers making a 315 tire
and demand is building faster than supply. I probably also paid shipping from the warehouse in the price.

I could have saved maybe $200 a tire if I had gone down to 12R22.5 but I like the wider tread pattern
and the bus handles like a dream with them even in places that I used to get slightly stuck with my RTS.

Sorry about that....

[TomC]

DrDave- the $550.00ea I got quoted was for Michelin XZA2 315/80R-22.5 18 ply tires out the door mounted and balanced-and they too have a 7 year carcass guarantee.  The 315/80 is made by every tire manufacturer, as it is the most popular tire to be used world wide on big trucks and buses (we are weird here-we are the only country that uses 24.5 rims!).

Please to everyone-when making a big purchase, it would be prudent to try the price out on us to make sure you're not being over charged.  Michelin tires (the best tire made) could have been installed for a gross savings of $1208 on the set of 8, if prices were checked with us first.  I apologize to DrDave using you as an example-not trying to be mean.  Good Luck, TomC