Rear axle/suspension problem-axle shifts when going on/off the gas

[Rusty Plum]

I recently bought a 99 4x4 auto 3.4 4 runner for my wife, and to use myself occasionally:wink2:. It has 168k and has a bit of rust, as well as some "deferred maintenance" over the years. I got it cheap and have already put some money into making it reliable. The other day I drove it for the first time in a few weeks and noticed that when you are coasting and apply the throttle, the truck veers to the left slightly, and when you let off it veers back left, each time having to counter steer to stay straight. It seems magnified at highway speeds (60-75mph). It also does the same but almost worse when turning the OD on and off at speed. I'm thinking rear control arm(s) on one (left) side? Has anyone else heard of or experienced this problem? If that is the answer, How difficult are the control arms to replace for an individual with good mechanical ability but lack of tools, work space, and motivation.

 

[D Farms]

One of my rear upper control arms lost a bushing on the trail, Im waiting on the bushing to come today actually, But its basically just bolted in using two large bolts. Id recommend a breaker bar and cheater bar and some kroil or whatever penetrating oil you have parts blaster or whatever. Mine is accompanied by a distinct clinking noise when I go over bumps.

 

[Run 4 Fun]

I personally have not had this happen and maybe someone else could chime in, but could this be symptoms of a stuck caliper or something in the brake drum on one side?

 

[KaliKid]

Im not sure if it is a rear control arm causing the issue. As far as replacement of them goes its is simple. Like stated before it is 2 bolts and a breaker bar or foot leverage is required to get those bolts loose. I suggest spraying them down starting a couple days before you tackle the project. Park on flat ground and start unbolting.

Have you checked tire wear and pressure? Also sway bar connects, etc?

 

[Rusty Plum]

I don't think it's the brakes, as it's fine when just coasting. The tires are good, and I don't hear any clunking noises hitting bumps. I'll check the sway bar but it supposedly had new bushings installed. D Farms, have you noticed any axle shift or sketchyness going on or off the gas?

 

[Run 4 Fun]

I don't think it's the brakes, as it's fine when just coasting. The tires are good, and I don't hear any clunking noises hitting bumps. I'll check the sway bar but it supposedly had new bushings installed. D Farms, have you noticed any axle shift or sketchyness going on or off the gas?

Gotcha, I misunderstood what you saying and thought you said it happens when you coast as well as applying throttle.

 

[D Farms]

I don't think it's the brakes, as it's fine when just coasting. The tires are good, and I don't hear any clunking noises hitting bumps. I'll check the sway bar but it supposedly had new bushings installed. D Farms, have you noticed any axle shift or sketchyness going on or off the gas?

Yeah it moves all over the road, I just got my bushing, it was the wrong one so I'll probably have to order a new upper link, however for now I found this special rubber tape, basically when you stretch the rubber it sticks to itself, the metal tube was still fine so I wrapped the rubber tape tightly around it, then trimmed it with a knife, it was actually just as firm as the stock bushing and it fit perfectly, it should hold for a few days till I can get the new upper link. the clank is gone now and it handles way better no slopping around.

 

[48HMSFAN]

My Experience

Hi. I had a similar problem to what you are describing. Basically anything over 45mph, when I would decelerate or get on the gas the back end swayed like crazy...to the point of wondering if I was going to roll the truck. Ended up being my rear LCA bushings. Long story short, I had the beefed up Toytec ones that used poly bushings, and within a year they were shot; even with regular greasing. I went with the Sonoran Steel as replacements, because Steve uses factory bushings; which he swears didn't require the maintenance of poly -- two years later; he is right. My Toytec ones lasted barely a year. Hope this hits you, that's probably your problem. It was so bad for me a normally 6 hour drive took over ten hours because I had be very careful with accelerating/decelerating past 45; basically I could do it but only by using the gas pedal in a very slow and steady manner...the brake above 45 was my enemy.