Oh no...not more tire/wheel ?'s

OP has a GM, but on my Dodge I have a 245/70R19.5 in the OEM location even with the larger MH diff cover, Hellwig Sway Bar, and Class V hitch.

Be sure to go with some sort of dynamic balance, I have Counter Act Balance Beads. The 19.5's are difficult to machine balance, and mine have been glass smooth so far.

It's about $2k for a set four 245/70R19.5 traction tires mounted and balanced on Vision rims. My only additional cost was the purchase of heavier shocks since the OEM ones did not dampen the extra wheel weight as well as when I had the lighter OEM wheels. My 275/70R18E tire is the same height as my current wheels and used as a spare. If I do get a flat on a 19.5, I can use the spare on the front and go for miles without worry. Fords can carry up to a 33" tire in the OEM carrier which equates to my 245's. I would hope most full sized trucks can carry the 225 in the OEM location. On a long trip I can carry additional spares in my trailer but have not felt a need to do so - The 19.5's are much thicker and ward off road hazards better.

bobndot wrote:
265'x16 won't support your rear weight ? I thought you looked into that when you bought this new camper . Those OEM GM wheels have a 3500/3700 rating. tires = 6830.

You might need a spare tire too, check into that. If you do, where will you carry it ? Under the truck in the OEM carrier ? Maybe , maybe not depending on the size.
You have limited slips in your 4x4 , so be careful with tire size on the same axle.
Look into swapping one of the fronts to the rear and maybe you could get away with running 2 diff diameters on the front for a short ride if you had to.
As I have found out , a lot of places are closed on Sundays , so finding a new tire to match a 19.5 might take a few days .


The new tires will raise the height of the whole package, you might feel that in crosswinds. I know it's only an inch but it's a 16 ft long inch on a SB truck.

I assume your warranty is expired . GM might not like the idea of a tire swap.

There are a lot of extra expenses that tag along with the 19.5's (mount and bal., off set )
Look at it on the Rickson Wheel website.

The trade value of your truck plus the money $4-5k spent on upgrading it to fit the new camper might be a down pay on a new or different (new to you) truck heavy enough to do what you need w/o mods.

Hi bob, yeah not ready for new truck...love our 06 Duramax.
The 265's have been great...but starting to show wear at over 30k miles...so starting to think about what is next and why not go to more capacity?
Already swapped out the spare for a 5th 265 (which does fit underneath).
Tx, Bill

19.5s aren't necessarily larger diameter and won't raise the vehicle height unless you want to. Even if true, 1 inch higher impact "described" in winds will be offset from the drastically stronger sidewalls.

$4-5K is high unless you went with the most expensive wheels and tires. In any case, I had a SRW because I couldn't make a DRW work for what I was doing.

I've never heard of any manufacturer voiding a warranty based on wheels/tires, but there may be one out there. GM might be it since they knew about an issue for 10 years and didn't (as has been reported) replace a $0.57 part. :)

265'x16 won't support your rear weight ? I thought you looked into that when you bought this new camper . Those OEM GM wheels have a 3500/3700 rating. tires = 6830.

You might need a spare tire too, check into that. If you do, where will you carry it ? Under the truck in the OEM carrier ? Maybe , maybe not depending on the size.
You have limited slips in your 4x4 , so be careful with tire size on the same axle.
Look into swapping one of the fronts to the rear and maybe you could get away with running 2 diff diameters on the front for a short ride if you had to.
As I have found out , a lot of places are closed on Sundays , so finding a new tire to match a 19.5 might take a few days .


The new tires will raise the height of the whole package, you might feel that in crosswinds. I know it's only an inch but it's a 16 ft long inch on a SB truck.

I assume your warranty is expired . GM might not like the idea of a tire swap.

There are a lot of extra expenses that tag along with the 19.5's (mount and bal., off set )
Look at it on the Rickson Wheel website.

The trade value of your truck plus the money $4-5k spent on upgrading it to fit the new camper might be a down pay on a new or different (new to you) truck heavy enough to do what you need w/o mods.

19.5's here, they are not "harsh" but you do feel the road more.

They are the smoothest tire I have ever ran, and also the most stable with a load. They really are worth the cost to upgrade to if you are heavy.

I only have a little bit of snow/ice time on these but I am very impressed.

I have the M608z in 245/70R19.5 LRG.

I went from 275/70R18E to 245/70R19.5H tires and have about 20k miles on my 19.5's:

1. Even if the tires have the same weight rating, the 19.5" have stiffer sidewalls making a loaded ride better and unloaded worse.

2. The GM trucks can use 225/70R19.5 without modifications. If you want to go up to 245 or 265, there are clearance issues in the front fender wells when at full turn lock unless you make modifications.

3. The 19.5's do well in mud, snow and ice because they cut through instead of float on top. Due to this characteristic, they do not do as well on soft sand or other areas where you want flotation over the top of the ground surface.

Im going to les schwab to get the front aligned today. I'll ask them about the new about 3900 pound stock wheel tires they are supposed to have now.

19.5s on my previous '06 Ford Srw were more harsh. Unbearable? No. My Hankook DH-01s had excellent traction. My change was from 18s to 19.5s. If you have the same diameter, the 19.5s will have quite a lot less sidewall height and with even stronger tires you will have less body roll.

I made the change for more room for error although I usually only ran 80 in front and 95 in rear. Don't forget you can't air them down that much. My current F450 came with 19.5s.