Starting to question safety...

I have a 2007 tacoma with a 3" lift and just recently put on my summer tires which are 275/65r16. Since i switched my tires, i find that every bump i hit, my truck swerves a lot. The worst is when on the highway. i'm now avoiding going beside 18wheelers because if they're beside me when i hit a bump, i might hit them.
Is this something i need to learn to put up with because of bigger tires??

 

Sounds like it's time for new shocks and maybe some front end work, too.

 

the extra width will tend to grab more imperfections in the road.

But with the proper amount of caster you should be good to track straight.

 

Do you have aftermarket upper control arms on? If you don't then I think that's the reason for the wandering. Your caster must be very low.

 

Definitely. +1

Unless they are LT tires, in which case the pressure should be significantly higher than the stock P tire pressure. Between 40 and 45 psi for a LT tire around that size (the Baja/Pro actually list 46 psi on the placard for their LT tires).

 

Could be more than a few things.Alignment,tire pressure,tire width,shocks,UCA's.

 

they are LT and they were put at 60 psi.
Before being at 60, they were around 25 and it was as bad.

 

i'm actually not even sure. i got it with the lift so not sure what previous owner did to it...
I wasnt swerving with smaller tires, is it only with bigger tires that i need to worry about the upper control arms?
Can anything bad happen...?

 

OK, well 60 is definitely too much. (And yes 25 way, way too low for an LT on road) An over inflated tire will in fact cause you to wander all over the road - essentially the wheel bounces too much so you are losing traction all the time. Since you are losing traction after bumps that matches up well with the cause being tire over inflation. So that could be part of your problem if not all of your problem.

Again, for an LT tire around that size you should be around 45 PSI. Manufacturer specifies 46 PSI for an LT tire of about that size, for both front and rear.

As others said alignment can play a big role too, but for starters lower the tire pressure to the manufacturer's specification and see how it behaves.

 

Great! thanks for your help!
Sorry for my ignorance but is there any way to tell is my UCA's are stock?

 

You can post a photo.

 

If you can't tell throw a picture up....you'll be surprised how fast one of these guys will answer your question for ya

 

Also, have you re-torqued your lugs?

 

My truck does the same thing when I have my aftermarket wheels (with backspace) on - same size tires, just wider stance and it tries to wander constantly. I'm lifted on stock UCAs, so I'm caster-impaired. No wander on stock wheels.

 

Those are stock

 

so what are my options?
is it a bad thing?

 

Well the options I think come down to:

- Install aftermarket UCAs. Head over to the suspension section for lots of posts to search regarding that.
- Adjust the lift down to 2" instead of 3" which will get you in better alignment range for the stock UCAs.
- Live with the current setup after driving with tires at proper inflation.

In general 2" of lift is worry free. At 3" of lift a lot of little things start to add up to potential problems (poor alignment, CV boots rubbing and wearing through, driver side bearing vibrating). Plenty of people run 3" with stock stuff and don't have significant issues, but many people also run into a lot of issues and start having to swap out components.

 

Take it in for an alignment. If they can't get the caster higher than 2.2 or so, you probably need after market UCAs. Light Racing UCAs are affordable.

 

Your best option is to put on UCAs. Maybe get someone's stock take offs from craigslist to see if that makes a difference. You live where there's winter, so running 2 sets isn't a bad idea anyway.

First things first, though. get your tire pressure to around 40 and see how much that helps. Both 25 and 60 are going to cause wander for opposite reasons. I'd get the lift down to 2.5 or lower if you don't do UCAs