I have a 2011 Tundra that is two months old. I am putting on some 275 75 18's, and the tire dealer is telling me I should get an alignment. Is that necessary? The truck has 3,800 miles on it.

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Any time you bump up in tire size it's a good idea to get an alignment done.

What about if you're replacing with the same size. My truck has just over 50,000. No hint of drift.

No alignment necessary for a change in tire size for what you are doing.

Check for uneven wear on the tires you have

Suspension lift, Yes...tires...no.

Replacing with the same size, No...as long as you do not see any uneven wear like the inside or the outside edge of the tires you are fine.

if there is a drift as you say it is usually due to the caster part of the alignment and it won't wear your tires out but is annoying and affects your handling. Also check for a hanging up brake caliper as that will cause drifting as well....and pay attention to the road you are on if it has a pronounced crown it could cause a drift as well.

How much were the tires? How much you willing to spend to see that they last you a long time. Now you have your answer.

Thanks guys. Tire wear looks very even across all of the tires. SE2000 - I hear what you're saying but with no drift and uniform tire wear I don't see spending $85 for them to confirm that the alignment is fine.

If 50k on 1 set of tires then I'd may skip it too. But if it is 2 sets, you would at least break even and cause less wear on your trucks suspension as well as tires

I wouldnt bother at that price. Every time I ever have tires put on, I get the alignment check. Many times even at rotations too, however, my shop doesnt charge for the alignment if they dont need to make any adjustments. I would say 9 times out of 10, the vehicles dont even need an alignment. Like others said, changing a tire size wont effect your alignment, adding a lift or replacing any components would require an alignment.