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Max Tire Size W/o Lift?

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ratthedd

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I've got an AV 2500 that I'd like to increase the stock tires to something bigger. Right now it has 245/75R16 which I calculate to be about 30.46" in diameter. Just eyballing the wheel wells it looks like I could go to about 33"s without a problem.

Anyone have any further info on this?
 

gandolphxx

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Welcome to big truck, small front wheel wells. Here are some observations, learned painfully. Stock wheels are real great, alloy/forged - will stand up to 95 psi inflation. Bad news is that they are 6.5" rims with an incredible 5" backspacing so that the fit. You can run 265/75/16 AT tires on the stock rims but they will look like a fat lady trying to get into a size 8 dress. Also keep in mind that you are carrying 6500lbs + need to distribute that weight - don't even think about going less than 2500 load rating.

I have Mickey Thompson forged wheels 16x8 on the rear - no problem there - had to go with 16x7 on the front to run with 265/75/16 tires - otherwise they will bind in the wheel wells - and that required tightening the torsion bars - which leveled the beast. The MT 16x8's have a backspacing of 4 9/16 which helps. I suspect that with MT wheels you could run BFG TA/KO's 275/70/16's - might be tight. You could probably run Pireeli Scorpion's at 285/65/16 if you want to race.

http://www.tirerack.com/index.jsp has the best research site you will find to check out "what ifs" - Discount Tire shops have been known to be cooperative to test things out.

Hope this has been of some use. ;D
 

Nick_R

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I have a 1500 avalanche with 285/75/16's with no problem rubbing. On the 2500's you probably will have to take the small piece of gray clading on the top of the wheel well off. I had to turn my torsion bars one turn , there is a high spot on the back of the front inner fender. That solved the rub spot. the 285's fill out the wells a lot better.

Nick R
 

zeeya2000

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What about with the 17"s. i have the 265/70's 17 and looks like i only have about 2" between wheel and rear fire wall.?
Would like a little taller, maybe a 285
 

gandolphxx

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Nick, the 2500 has a different set of front end problems than the Z71 - it is not the silly fender flare - it is the wheel well itself and the frame stiffeners. I am looking at 285/65/16's as an alternative.
 

BLKJACK

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What's with you guys? This is the 3rd subject post on the same topic ..TIRES! So look at the other ones too. Here is something I found out through searching tire mfg. web sites. The same size tire can differ in diameter between manufacturers. For example...Dunlop 285/75/16 is 32.7" diameter. The Bridgestone is 33.1" The Goodyear is 33.0" Also, the charts on TireRack and the manufacturer's charts don't always agree. There is alot of different sizes that will fit, some will need a torsion bar adjustment. Also, a taller tire will throw the speedo off a couple of mph. :eek:
 

Chief

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ahhyeah said:
If you want 20s, they fit easy...

I think these guys are talking about tire size and load issues not wheels. ?That what these 2500 owners do ?;D

I think the guys around here know that 20's are fine for a 1500 ... I almost went with 23's. ? We'll have to wait and see what Santa's brings.

AV_z66_20s.jpg

ps - love your website >:D
 

jackalanche

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and check out ahhyeah's hood - damn I was thisclose to getting the same one a month ago, thought I woud somehow get out in front of the rest of the modders, and now I am just a wanna be modder again! Nice ride ahhyeah.

As for wheel rim size, most of us know that plenty of rim sizes (20s, 21s even 23s) will fit, it is just a question of how low profile you want to go. While it might not seem obvious to a pure streeter / rollin' wid da homies set, the "max tire size without lift" topic is usually (in truck terms) a question of how much rubber (off-road capable, usually) can I get in there before I have to lift the thing for more clearence. That's why the speculation on tire sizes, which are expressed in such a way to allow us to understand the OD (outside diameter) and section width - critical for fitment issues. Plus, those looking into this topic are often looking for offroad capabilities (or at least the "look' of off-road capable), and a low profile tire (required if you go up there in rim sizes) is a poor choice in that regard (rims will dent, low profile tires are not found with agressive tread, etc.), not that I don't appreciate the look, if that is your thing (nod to Goo).
 
W

WhiteAVZ71

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So what sizes have people got?....tires that is. Overall diameter stock I think on a 1500 Z71 is like 32.5" Anyone gone taller?
 

Chief

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White,

My new O.D. on my Goodyear Eagle GT II's is 31.2". ?My stock Z66 Wrangler HP's were 32". ?I have actually lost 8/10ths of an inch. ?

Let's not get into a size and performance discussion now ?;D

I never did get my speedometer adjusted. ?Let's see what the math says:

(New Tire Diameter / Original Tire Diameter) X Indicated Speed = Actual Speed with new tires.

(31.2" / ?32") X 55MPH = 53.6 MPH Actual Speed with new tires.

So I am getting better simulated gas mileage and putting less miles on my truck ????

goo929


ps - my tire specs are from Tire Rack
 

simtechray

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WhiteAVZ71 said:
So what sizes have people got?....tires that is. ?Overall diameter stock I think on a 1500 Z71 is like 32.5" ?Anyone gone taller?
My calculator says stock Z71 (265/70R17) tires are 31.6 inches OD which my tape measure verifys with 34 psi in them.
 
W

WhiteAVZ71

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Ok so I may be off on initial measurements but whats the tallest anyone has on their ride with no torsion bar tweaking?
 

greenmachine

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See the "4x4 and Off-Road" section for recent discussions about this very thing. Short answer, "some" 285/75R16's will fit, some won't. Depends on the tire and the rim width. I personally know a 285/75/R16 BFG All-Terrain on stock 16" (16x7?)rims did NOT rub, but a Goodyear MT/R of the same size on 16x8 rims DOES rub. I believe the MT/R's are 32.4"x11.4" tires, so you need something "just" smaller than that.
 

jackalanche

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well let's recap what we know - and this is for the 1500 (G-xx says the 2500 has a different amount of clearance in there b/c of frame stiffeners).

The stock Z71 rubber - well I am rather sure it doesn't tip the scales at 32.5 - oh I see another poster just put it straight at 31.6 for the 265/70R17

I am running 275/70R17 MT/Rs - with a 32.4 OD and a section width of 10.9 (get both #s, I think it is the section width that is causing the rub in the next paragraph, since we ain't bumpin up against anything.)

Crexis and Greenmachine both just put 285/75R16s on - one using BFG's KMs (the Mud Terrains) which show up with a 33.1 OD and a section width of 11.3, the other using the MT/Rs which shows an OD of 33 and a section width of 11.2. And they both report a slight rub on some bubble in the front wheel wells at full crank.

I may have pushed it as far as possible without the little rub (@ roughly 32.5 OD and 11" width), but I have heard another poster with the same rub that Crexis and Green have banged/trimmed it and made the issue go away without too much trouble. So I bet they too will call it a minor tweak to get their rubber in there
 

gandolphxx

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Just a note to consider, check the min/max rim width on 285 tires and also note that no matter what the local tire guy says, they may not fit your stock wheels properly, you may eventually pay the price in crowning and stability.

This will be different for the 1500 vs the 2500 - different wheels, loading, etc. Check the mfgr's web sites for the reccommneded width range of the tires.

1500 Z71: 17x7.5
2500 4x4: 16x6.5

My $.02
 

BigE74

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I have 20's on my 1500 with a nice 305/50. I think that is about as big as you can go. In the back you could go a little bigger, but the front is close but it does not rub at all.
 

metalguru

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I have fitted 265\70\16 H rated tyres with no difficulty onto standard rims.

I have had Bridgestones, Dunlops and Yokohamas all without problem.

The Dunlop Grand Trek PT1 tyres, however, disappearred in 11,000 miles!
 

MountainLife

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I have 285/75/16 BFG AT's on my 2500 they are perfect with 0 rubbing they equate to just about a 33 I believe
 

8100PULLER

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OM MY 2500HD YOU CAN PUT 265/75/16 ON 16X8 WHEELS AND IT DONT HURT ANYTHING....285/75/16 ON 16X8 REQUIRES SOME TORSION BAR CRANKING
 

8100PULLER

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AND GUYS WHY ARE YOU ALL SO AFRAID TO CRANK ON THEM BARS....JUST DONT GO TO EXTREME OR YOU WILL BEND YOUR FRONT BAR UNDER HARD ACCELERATION OR HEAVY PULLING AND THAT IS NOT HEALTHY FOR A SET OF TIRES
 

whitethunder

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ratthedd said:
I've got an AV 2500 that I'd like to increase the stock tires to something bigger. Right now it has 245/75R16 which I calculate to be about 30.46" in diameter. Just eyballing the wheel wells it looks like I could go to about 33"s without a problem.
Anyone have any further info on this?

Okay we have been through this before! if you do a search you should find loads of info on this topic.

i appreciate your request but in response whay have you not registered?

if you look at my signature you will see that i have increased the tire size up 2 steps!

I have the stock rims and they are excellent rims have been off road through snow and all kinds of terrain with no problems.

If you want the largest tire you can get with out a lift kit these are them!

Bridgestone 285/75/16 A/T Revo's

you will have to increase the torque to compensate for the increase in diameter and you may get a little rubbing while in reverse or while cranking the steering wheel i have had these on for 6 months and they are great!

Good Luck!
:B:
 

irontrain

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whitethunder said:
ratthedd said:
I've got an AV 2500 that I'd like to increase the stock tires to something bigger. Right now it has 245/75R16 which I calculate to be about 30.46" in diameter. Just eyballing the wheel wells it looks like I could go to about 33"s without a problem.
Anyone have any further info on this?

Okay we have been through this before! if you do a search you should find loads of info on this topic.

i appreciate your request but in response whay have you not registered?

if you look at my signature you will see that i have increased the tire size up 2 steps!

I have the stock rims and they are excellent rims have been off road through snow and all kinds of terrain with no problems.

If you want the largest tire you can get with out a lift kit these are them!

Bridgestone 285/75/16 A/T Revo's

you will have to increase the torque to compensate for the increase in diameter and you may get a little rubbing while in reverse or while cranking the steering wheel i have had these on for 6 months and they are great!

Good Luck!
:B:

True but we should have answered him sooner. ;D
 

Turbo_Av

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I am running LT255/85/16 Kelly MSR's (33.3" as per Kelly website)no rubbing at all until I put on my 16" x 8" AR's I had to push in the inner fenders and trim my front mud flaps. I also do have the 1/2ton torsion bar adjusters installed and my front is about 3-inches higher than stock(with the tires)
 

SVT F15O

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Can anyone tell me if I would be able to get away with 285/75-16's on a 16x8 rim, if I do the Ford key install and crank the bars>??? I am looking at the American Racing Mojave Teflons(16x:cool: and 285/75-16's Goodyear MTR's. Any advice or suggestions>??? Thanks in advance. -Mat- :B:
 
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