Adjusting to the 2002 Tacoma 4X4

[Rod in Smiths Falls,]

My '95 4Runner still drives better than the new ride. Both are 4 cylinder, 5 speeds. For one thing the old Runner uses quite a bit less fuel, but the main problem with the Tacoma is that after three tries I can't get the tires to balance. They're new, slightly oversized 16" all season tires that the Pittsburgh used car dealer slapped onto it to sell. The brand escapes me right now.

Either the local tire guy is hopeless at his job or oversized tires are inherently hard to balance, or they're picking up gravel and throwing themselves out of whack all of the time.

I can't drive the truck at sixty miles per hour after the latest session in the shop. Fifty's o.k. and seventy's good, but fifty-five to sixty-four is very rough.

I'm using the pressures listed on the door post and running them at 26 pounds, front and back. The tire guy insists I should have at least 32 p.s.i. in them.

Suggestions? Comments?

[ddnail]

Hi Rob, this sounds kinda familiar to me. I actually have some quite over sized tires on mine, (285-75-16's) and they are balanced perfectly. Now, that said I know several people have had issues with theirs because they are "hub centric". There is a difference in the balancing techniques. If you do a search for "hub centric" here you'll find a wealth of info further explaining the symptoms and cures.
As far as the tire pressure, I would run at least 35psi. in them. I know Toyota recommends 26psi but that is assuming you are running the stock size tires on it. I would run what the tire mfg recommends or at the very least 35psi.

[kathyricks]

The 26 PSI will definately give you a smoother ride, plus lower pressures help reduce wear and tea on the suspension. Aftermarket wheels commonly don't balance as well as factory wheels and the ones I had also induced a pull to the right. So I went back to factory wheels to solve freeway ride smoothness and directional stability issues.

[The Phoenix]

It's possible the tires themselves are out of round. It's not uncommon to find a few bad tires in the batch. Does it feel like it's only coming from one side or both?

[Rod in Smiths Falls,]

I turned around on an icy road today and headed for the nearest tire store for a re-balancing, as I could hardly keep the thing on the road.

The guy said all four were out of balance; most likely the previous tech's machine needed to be recalibrated. He further suggested running 35 pounds in them, regardless of the spec's from Toyota.

Away I went on a lumber wagon. Every crack in the pavement, bump, or wheel wiggle transferred to my wrists and spine. The balance was a bit better, though. After a hundred miles of bumping along I aired the fronts down to 30 and the backs to 32. Somewhat better, though there's way too much abuse of the driver from those tires or the truck.

It's hard to tell if the vibration is coming from one point or another. Much of it is intermittent. For example, the tires can be running nice and smoothly and then thump for a while after a turn at freeway speeds. With a two thousand miles on them they're too new to have belts delaminating.

My 4Runner on 235R15's runs much more smoothly, and it has 373,000 km on it. Do I need to load the Taco until the springs bend in order to have a decent drive?

[The Phoenix]

Are you driving on concrete roads? They usually make driving harder. The leafs are not the culprit here.

[Rod in Smiths Falls,]

The roads are all asphalt in pretty good condition.

The more I think about it the more likely the rims seem the culprit. One rear is bent a bit, though on my 4Runner a similar out-of-allignment rim has caused no problems. On a smooth highway at 60 mph this afternoon I could see the box vibrating in time with the thumping of a back wheel.

I think the alloy rims came on the truck when purchased new. They have a Toyota logo on them, at least. I looked through the purchase documents which were included with the owner's manual and couldn't find any reference to the option list, though.

If the rims were a bit loose on the wheels, they'd act just about the way they are doing.

How would a bent axle behave?

[The Phoenix]

A bent axle would cause a constant vibration and you would really notice it at that point. If you take a photo of the wheels I can tell you if they are OEM Tacoma wheels. I know just about everything regarding these trucks since I've owned 4

[Rod in Smiths Falls,]

They're OEM Toyota wheels. There's an outfit in Ottawa which has one of the balancers which pushes a roller against the tire while it spins. I've booked it in for a session there on Tuesday morning.

Today on a smooth stretch at 60 mph I observed the rear cap carefully. The left side vibrates quite visibly in the mirror. The right sits still.

The hop is quite noticeable, even dangerous, when there's a bit of snow on the road.

BTW: do all pickups hop off sideways when they hit washboards or wet railway tracks? That's a P.I.A.

I talked to the local Toyota service manager today. He has no problem with a conventional balancer for Tacoma and 4Runner wheels.

By a process of elimination I'm coming down to blaming the left rear wheel. It's the one with observable runout when on a conventional balancer. Next step might be to steal the wheels off the old 4Runner for a test before my friend buys it this weekend. It has very smooth-running tires.