Piston Slap: Taking Control of Torque Steer?

M.D.K. writes:

Good Afternoon. This will be my third query to this column, the first being an ill advised plan to put my wife in an old Mercedes hatched in an Afghan Bunker, the Second being for our Afghan Trailblazer that wouldn’t run. The Benz never materialized (thankfully) and the Trailblazer was made to run reasonably well with a fuel filter and removal of the clogged catalytic converter (The EPA man wasn’t coming to Bagram). Sadly about a week after we got the Trailblazer running they collected it in an effort to go to an all diesel fleet. It was replaced with a TaTa pickup.

This actually pertains to a vehicle in my own fleet, my wife appliance grade 2007 Hyundai Tucson.

It is a 2WD 2.0 4 cylinder automatic that has begrudgingly earned my respect for the fact that it has gone about its 94,000+ miles with the timing belt and seized tie rods courtesy of upstate NY winters being its only dealer trips. Tires, Oil, Gas, and brake pads are it otherwise.

My issue now is that it exhibits torque steer like crazy. Doesn’t seem to be an alignment issue as I just had it done (hence the new tie rods) and it is straight so long as your foot stays off the gas. But press the gas, even at highway speed and it tries to turn right.

My research seems to point to the lower control arm bushings as the culprit. I have no suspension clunks or anything though. The motor mounts also look good and the tires are of the correct size. The struts were done a year as well. I know FWD vehicles will exhibit some torque steer but I have had this vehicle since new and this is abnormal.

My plan would be replacement lower control arms since there is some rust on them anyway but I want to make sure I’m not missing something else here. The car is paid for and has no other issues so I’d like to figure this out. We generally take it on our long trips so the constant tug on the steering is annoying. Just want to make sure I am not missing anything.

Sajeev answers:

Thank you for writing again, I do love my repeat customers!

Since you replaced the tie rods, the torque steer’s source is either a control arm bushing or a ball joint. Or maybe both? No matter, if one side is bad then the other is ready to fail. Whatever failed, replace it in pairs.

Wow, that ended pretty abruptly.

(crickets)

Bonus! A Piston Slap Nugget of Wisdom:

Always remember that suspension parts go bad with time, but modern cars have it worse for a few reasons. Take the increasingly horrible condition of roads in this country. And oversized wheels with rubber band thin sidewalls: offering no cushioning effect on our (increasingly horrible) roads.

And maybe it’s my family’s two Mercedes products that ate lower control arms with less than 30k on the clock, or my friends with control arm consuming BMW and VAG products from the last decade, or the numerous related Piston Slaps ( here, here, for starters)…but suspensions don’t last like they did 20-ish years ago.

And while suspension lube service intervals must remain in the bad old days of wide whitewalls and “separate but equal” segregation, one must never forget:

What’s that? You say video game Panther Love shall never prove my point?

Well excuuuuuuuse me!

[Image: Shutterstock user temp-64GTX]

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.