Shim Kit for rear toe adjustment?

I've used this: EZ SHIM Online Application - SPC Alignments

It lets you adjust toe and camber at the same time.

Bob Wilson

 

Funny that everyone complains about their rear toe - I got an alignment today, and the rear-left toe is out of wack as well - +0.35 toe-in (limit is -0.01 to +0.29). Right rear toe is okay - +0.02 toe-in, which makes +0.37 total toe. The total toe however in spec, since it needs to be within -0.02 and 0.58 according to this alignment sheet in front of me.

I got the alignment done at the dealer. I really wonder if wvtoyotatech is correct in this thread below that the techs may not be doing the alignment right:
http://priuschat.com/forums/gen-ii-...e-learned-regarding-prius-rear-alignment.html

Just a thought

 

I had a lot of rear toe problems with my Gen2. Toyota dealer replaced the rear axle beam and ended up making it worse, it did not have enough toe in. The car really handled badly on the highway, wondered all over the road and when the wind was blowing you could change lanes without moving the steering wheel. It felt like the back end wiggled around and you had to make constant steering corrections to keep the car going straight.

Priuschat poster Galaxee and her DH helped me out by sending me a pattern for some shims, he was a Prius Tech at the time and had seen the problem before. I made some .005 and .010 shims out of shim stock from the hardware store and tried a couple of times having the alignment checked each time. When I got each side about in the middle of its range and had the front set with just a hint of toe in it fixed all the problems. I sold that car a couple of years ago but I'm confident the new owner got a pretty good driving Prius.

Fortunately I have had none of those problems with my Gen3, it's one of the best highway cars I have owned.

When I was having my problems I knew nothing of the shim kit Bob W. posted the link to, it might have made things a little easier.

 

tumbleweed:

How bad was the toe before Toyota replaced the axle and made it even worse? I am just wondering if the +.35 toe-in on my rear-left wheel is something to worry about. The rear-right wheel is only .02 toe-in, so no worries there. Open to any opinions/suggestions...

 

I sold that car about 3 years ago and passed on all the documentation to the new owner. I do remember one side was toed in ( + direction) to far and out of spec by only a small amount, the other side was within specs. As I recall the spec for rear toe on that car was +.03 to +.27 degrees on each side, mine was about +.31 on one side. At that point with the original axle it drove OK and if the dealer had left it alone it would have been fine, maybe a little to much tire wear is all.

The new axle they installed was toed out to far ( - direction) and that's what made the car unstable. But at that point they said they had "fixed it" and would do no more. So I installed shims to toe both sides in toward the middle of the range, maybe a bit more and get them about the same. I think I ended up about .20 on each side. That solved the problem.

That was a Gen2 (NHW20) and had drum brakes on the rear and the shims fit between the axle and the brake drum, easy to install. The shims were designed so they change the toe without effecting the camber, at least not by much. I no longer have the pattern but I'm sure the Gen3 (ZVW30) would require different shape and size ones anyway.

I did learn that as far as stability and drivability are concerned a little to much toe in (higher + number) is better than not enough. At least that was true on the Gen2 Prius, and I suspect it pretty much applies to all street cars.

As to your car I think if the +.35 degrees were evenly divided between each side you would be fine, say .15 to .20 degrees toed in on each side. I don't know if it's possible to to relocate the axle by a small amount or not. I really wish they would have given us independent rear suspension with individual toe and camber adjustments on each side such as the Camry has, oh well.

 

Sounds to me like your delaer did not properly center the rear axle beam prior to your alignment. This causes multiple issues because your front alignment numbers are based off the rear numbers.

 

Does these alignment specs seem as if they did not properly center the rear axle? As far as I know, I have not hit any significant potholes. Bumpy roads, sure, but no deep potholes or anything. Appreciate any comments!

 

Appears they did *not* properly center the rear axle beam, looks like they made a right turn onto the alignment rack. I can take a video at work monday of how we center the rear axle beam if you'd like.

 

I would like to see the video or even a text description.

Thanks,
Bob Wilson

 

If its not a bother, that'd be great.

 

Yes please, I would like to see that also. I never knew it could be centered without taking the bolts out and moving it around.

 

I went back to the dealer yesterday. I went to the service advisor, and presented the possibility that the rear axle may not have been centered due to turning onto the alignment rack. He responded however that his alignment rack was "straight", in that all they do is drive a car straight onto the alignment rack from the "entrance" (whatever that might be), so no turns would have been made. He also said that I need not worry, that I am not going to have excessive wear or anything on that rear tire.

So I guess I'm back to square one again, unless the dealer somehow still made a mistake when checking out the alignment of the car.

I am almost debating taking the car to a proper alignment shop and seeing if their alignment gives the same results! If it does, I wonder if I should write to Toyota - on deaf ears of course, even though my car only has 7k miles on it and its only been 6 months from purchase date.

 

It's always a good idea to get a second opinion. When I was having alignment problems with my NHW20 I went to two different Toyota dealers and got two completely different sets of alignment numbers, no adjustments were done in between. I went to a local tire shop which has a good reputation and their numbers agreed almost exactly with one of the Toyota dealers, both had fairly new Hunter alignment equipment, I went with the two that agreed.

 

Even if there is no direct turn onto the alignment rack, effort is required to ensure the beam is straight. Backing out of the spot you parked the car and then just driving on the rack will not properly center the rear beam.

 

I'll get the video as soon as I can, hopefully Monday. It is very busy this time of year.

 

Hello. I grabbed a car off the lot to use in this video as my exhaust is too loud and it gave me another chance to play with the Solar Roof.

First video shows why centering the rear beam is important as it is a 180 deg turn into where our alignment rack is.

Second video shows the procedure that we use (we've proven its effectiveness) to center the rear axle beam prior to alignment. It involves going back and forth and "slamming" the brake pedal. The last few back and forth motions before pulling onto the rack are with the parking brake slightly dragging.

 

Josh - do you know of any reference document that I can refer to or use to help out my dealer to be able to check out the alignment properly, or at least convince them to do another alignment just to be sure of their results? It would be great if Toyota somewhere has a document that says "be careful when doing alignments of all cars with torsion-beam rear axles - make sure to do this/that". Otherwise it'll be hard to convince my dealer to take a 2nd look at this. So far I like them, however as with any business sometimes you need to bring some evidence to convince them to your perspective.

Thanks again!

 

I highly suggest you show them my video. I did my pre-autocross alignment check on my 2010 today during lunch and I grabbed a pic of what the alignment numbers should look like if the beam is properly centered.



Toe and camber numbers may very slightly but as you see everything should be evenly split. I feel my pic is evidence enough that a properly centered rear axle beam makes a significant difference is alignment measurement numbers.

 

In the sense you are using "centered" it can't. I haven't read of anyne loosening a Prius rear suspension and moving it to one limit to average out a an uneven toe problem. It's not in my Toyota repair manual either. Some car companies manuals have it as part of an alignment problem solving procedure. We may have some potential there.

What Josh is doing is averaging out all the elasticity and slop in the system, not adjusting it. I wish there were a few more shops with techs that paid that much attention to what they were doing.:rockon:

Josh, do you have any comparison numbers that compare just driving it on the rack with the method you use?