"Floaty" steering on interstate - Tires or Alignment?

[Throwback]

I bought my '14 TE with 25k miles on it a month ago and within one week had the OEM Dunlops removed in favor or BFG KO2 265/70/17 LR:Cs. I'm running 38psi at the moment.

Unfortunately, I don't remember what the truck drove like before the tire change enough to know if it acted this way on the OEM tires.

When driving at 70mph on the interstate it feels like it takes a lot of attention to keep the truck in the lane. It rides smooth as silk and doesn't fight or drift in the lane per say, but I'm not able to just kick back and rest my wrist on the wheel and cruise. I have to pay attention and constantly make adjustments or else the truck feels like it's wandering around the road.

I've played with the tire pressure and while the ride gets firmer or softer the "wandering" isn't really effected. Does anyone know if this is a trait of the BFG tires, or if this is something attributed to the alignment?

I had chalked it up to the LT tires and Discount Tires has a set of P265/70/17 Cooper AT/3s waiting on me to swap out, but I'm not certain that will change this cruising characteristic.

Any ideas?

 

[03_4x4Runner]

My 14 Limited was like that when I bought it new. I had the dealer align the front and it was fine after that. Mine is the same with my K02 or the stock tires.

 

[vjack]

No harm in checking the alignment. Most dealers have those fancy alignment cameras that will do a free & immediate alignment check when you drive through the door.

If the alignment comes back OK you could look at the tires. I don't have KO's but A/T tires are not known for their stability at high speed.

By the way why are you driving with your tires so over-inflated? I would drop them down to the Toyota spec (32 psi probably; check your driver door jamb) and see if that handles better. Over-inflated tires might make your steering twitchy because of a reduced contact patch.

 

[wfo9]

Most likely needs more + caster in the alignment. More caster makes it want to go straight on its own at speed.

 

[mcox522]

I put stock KO2s on my 2016 TEP when it had 100 miles one the OD. I run them at 39-40 psi and they drive great on the highway. Very smooth and no wandering. My guess would be an alignment issue...

 

[Throwback]

Thanks. I'll see about getting an alignment at the dealer and will probably go ahead and swap out for the P metric Coopers since I do 95% or more highway driving. My off roading doesn't involve airing down or rock crawling, just first service road exploring. Maybe the tire change will help the highway manners a bit.

Does the factory alignment spec set the caster to track straight at highway speed?

 

[1engineer]

Thanks. I'll see about getting an alignment at the dealer and will probably go ahead and swap out for the P metric Coopers since I do 95% or more highway driving. My off roading doesn't involve airing down or rock crawling, just first service road exploring. Maybe the tire change will help the highway manners a bit.

Does the factory alignment spec set the caster to track straight at highway speed?

Have them set caster as close to 4 as you can.

 

[Ducmonsta]

No harm in checking the alignment. Most dealers have those fancy alignment cameras that will do a free & immediate alignment check when you drive through the door.

If the alignment comes back OK you could look at the tires. I don't have KO's but A/T tires are not known for their stability at high speed.

By the way why are you driving with your tires so over-inflated? I would drop them down to the Toyota spec (32 psi probably; check your driver door jamb) and see if that handles better. Over-inflated tires might make your steering twitchy because of a reduced contact patch.

The "alignment cameras" I've seen while driving into the dealership check in area are a gimmick. Maybe there's some new fancy thing out there that I'm not aware of.

The tire pressure on the door jamb is the recommended tire pressure for the factory installed tires. Once you replace them with non-factory spec tires, all bets are off. I ride comfortably on 42-45psi in my E range tires. And they are FAR from over inflated.

 

[Saker]

I have to echo all here about getting the alignment checked. Period!
I run the same tires as you (44psi), lifted and have no issues and my caster is at 3.3 degrees. Wish it was higher, but it's maxxed because of the lift....

Take it in and have them align it.

 

[philsey]

Have them set caster as close to 4 as you can.

Take it in and have the align it.

I had your same situation (as have many, many others on here) and ^^ this is exactly correct.

However, know this: The 4R is within factory specs at something (I forget) well below +4 degrees, and you may get told it's OK. You need to be sure to get before/after printouts and discuss this before alignment to insure the shop knows what you want.

I went to my dealer SM and discussed it. He knew what I wanted and why. That was 6 years ago and it has driven perfectly since.

 

[Saker]

I had your exact (as have many, many others on here) and ^^ this is exactly correct.

However, know this: The 4R is within factory specs at something (I forget) well below +4 degrees, and you may get told it's OK.

That spec is 2.5° - 4° for my 2014

Here is the spec sheet on mine....

 

[e60ral]

i have mine at 3.3 and it feels much more confident than it did before, that was the most dealership would raise it to and i'm not sure if that was because of their specs or mechanical limitations (i was going to ask since i requested 4, but decided to test drive first before making a big deal about it and it feels okay now)

 

[Throwback]

How does that affect tire wear?

 

[Simpleman74]

How does that affect tire wear?

doesnt as long as everything else stays within spec

 

[1engineer]

How does that affect tire wear?

It doesn't. Read this Tire Tech Information - Alignment

 

[Brandon_Reed]

I had the same feeling in my '16 trail. I had them check the alignment at 10k and it was off on a couple measurements now it feels much more stable.

 

[Throwback]

Good link, very clear and basic explanation.

I had the dealer do a full alignment and ended up at 3deg caster. It was about 2deg prior. The toe-in was out of whack as well. Possibly placebo effect, but the wandering effect seems to be significantly lessened now.

 

[1engineer]

Good link, very clear and basic explanation.

I had the dealer do a full alignment and ended up at 3deg caster. It was about 2deg prior. The toe-in was out of whack as well. Possibly placebo effect, but the wandering effect seems to be significantly lessened now.

No placebo effect as there is a big difference in 2 and 3 degrees. I ride mountain bikes almost daily and caster on a vehicle equates to head tube angle on a mountain bike. Just a few degrees difference on the bike makes a huge difference. Unfortunately you need to know that up front as they are not adjustable lol. It also does the same thing... twitchy versus stable.

 

[Jhalko]

No placebo effect as there is a big difference in 2 and 3 degrees. I ride mountain bikes almost daily and caster on a vehicle equates to head tube angle on a mountain bike. Just a few degrees difference on the bike makes a huge difference. Unfortunately you need to know that up front as they are not adjustable lol. It also does the same thing... twitchy versus stable.

Fox TALAS and other adjustable suspension forks? Not changing wheelbase but will change positioning and angles by flipping a lever.


When I replaced my UCA's, I went from caster at about 2.1 to 3.7, made a very nice difference on the highway.

 

[Throwback]

No placebo effect as there is a big difference in 2 and 3 degrees. I ride mountain bikes almost daily and caster on a vehicle equates to head tube angle on a mountain bike. Just a few degrees difference on the bike makes a huge difference. Unfortunately you need to know that up front as they are not adjustable lol. It also does the same thing... twitchy versus stable.

When I was doing a lot of motorcycling I saw the same thing. A lot of guys would lower the front end of a bike by sliding the fork tubes up in the triple trees an inch or so and didn't realize how much more twitchy it makes the bike. Very dangerous sometimes.