Are different front and rear tire size on 2009 Trailblazer LS are acceptable?

[gkhanna]

I lifted 2 inches of the 2009 Trailblazer LS last year to install bigger tires 265/65/R17 (rare size tires) for off-roading.

 

Recently after experiencing a puncture, I changed the rear tires to 265/70/R17 (easily available size).

 

I know this minute difference is fine for 2W and 4 Auto but will it cause any issues while off-roading in 4 High or 4 Lo?

 

Does the 2009 Trailblazer LS with a 4.2 engine have 50/50 lock at the central differential?

 

Thanks in advance.

 

[diyer2]

Why do this?

[gkhanna]

15 minutes ago, diyer2 said:

Why do this?

Good question, I did this out of ignorance as the same size wasn't available.

 

So checking if 1-inch variance will cause trouble with 4 high or 4 low?

[mjm-1957]

Yes, all tires have to be the same size.

[gkhanna]

Thanks @mjm-1957 , much appreciate your help and advice.

[newdude]

You need all 4 of the same size.  That much diameter difference is likely to cause binding or mechanical issues with the 4x4 and transfer case.  

[Jsdirt]

As others have already mentioned, ANY vehicle equipped with a transfer case MUST have 4 matching tire sizes.

[Z45]

6 hours ago, Jsdirt said:

As others have already mentioned, ANY vehicle equipped with a transfer case MUST have 4 matching tire sizes.

The should all be the same brand because different brands may have different circumferences (or radius). While a vehicle is traveling down the road, the tires rotate a certain number of times per mile depending on the true tire radius. If all the tires do not have the exact same true radius (due to load, tire pressure, wear, build variances...), they will turn at slightly different rates. Also, unless the vehicle is traveling in a perfectly straight line, the front and rear axles are traveling in a slightly different arc, which means the front and rear axles are traveling at slightly different average speeds.

[Jsdirt]

Yep, great point. I've seen plenty mix-matched in my time turning wrenches, but ideally you'd want them all the same brand. Sizing is the most important, with a matching brand second.

[diyer2]

I wouldn't wear two different shoes but some would.