Minimum tire depth before replacement

[Keith Hughes]

We tow our 2021 Montana 3121RL rig with a 2021 GMC Sierra 2500 Diesel 4WD truck. This is the first time we’ve owned a truck and want to keep it properly serviced. The truck is 3 years old with almost 30,000 miles of which 13,000 are towing miles. What is the minimum tire tread depth you would not allow your tires to go below to ensure safe towing with the truck. Tires are now at 4/32 front and 5/32 rear.

Thoughts and recommendations?? TIA!

[Mikendebbie]

I always go by Abe Lincolns head on a penny. I'm sure someone will have a more scientific answer.

[mlh]

I wouldn’t go much more than 1/2 of the thread left. Sure it’s legal to go less but it isn’t as safe.
Lynwood

[Foldbak]

There are wear bars. Don't get to them!

[MandK]

Legal is 1/16” or right on the wear bar but I buy new at twice that, 4/32.
My truck, also a ‘21 came with Michelin LTX A/T, has 39,000 on it and they are at 9/32
I have bought 10 new pickups since 1976 and the factory tires have always rode the best and lasted the least. Some of them barely made 30k. These I am impressed with. Good ride, quiet and they should go 60k.

[RMcNeal]

The penny gauge is a good indicator. I taught that to my daughter years ago. The measurement I've always used is 3/32nds inches. I have a tread depth gauge for readings in 32nds of an inch.

[bethandkevin]

Are you measuring to the bottom of the water channel or the wear bar? To the wear bars is generally 2/32". Personally, I wouldn't want them that low. Most LT tires are 13/32" or more when new.