Rear Alignment Shim and Hub Bolt Torque

Mike, Thank you for finding out that the commonly recommended shims have problems and for finding us a workable substitute.

Some of the wander may be due to the goofy rubber bushings that allow the rear axle to rotate left and right a bit.

 

How would I go about knowing which shims I should purchase to correct my toe reading and how would you install these? IIRC the measurement in the LR of my car was -.48.

Anyone know where I would be able to order these shims online?

The Toyota dealer that did my alignment pointed out that my LR was a bit out of spec. When I asked if they could correct it, they said they couldn't, and recommended that I speak with a bodyshop to see if they can install shims and correct. Total crap is what I assessed their explanation as.

 

Sounds like they are lazy and don't like a challenge. I'd find a different dealer to work with.

Mike

 

The total crap part is that they said body shop instead of alignment shop. Your dealer did you a favor by not doing the work because dealer shops are primarily parts swappers.

There are shims on the market that don't work and some that do. See earlier posts in this thread by The Critic. He listed a NAPA part number for 0.25 degree shims.

 

Thanks xs650,

I did read through his posts. I'll give visiting NAPA parts a go. Was hoping I could save a trip or two and find a place that could ship them to me.

 

Take that NAPA part number and put it in a Google search. You might find an online seller or possibly NAPA has online sales

Mike

 

Okay success. Thanks guys. I was able to find the parts online and have a NAPA store down the street from me

Could I get some advice on how I should correct the toe? I'm not alignment expert. NAPA has 1/2 and 1/4 kits. It makes sense to me to get the 1/2 kit to correct the RR toe and the 1/4 kit to correct the LR toe and get me the closest to 0.0 +- .02.

RR Camber = -1.0 LR Camber = -1.4​

RR Toe = +0.48 LR Toe = +0.25​

If I were to continue to drive with that toe setting for 1,000+ miles, would I ruin my tires?

 

What caliper spacers, if any, did you end up using?

 

Thanks Critic for this great write up. Believe it or not, this thread was linked on ToyotaNation in the Corolla specific discussion.
My problem is with a 03 Corolla. I just came back from alignment check and Firestone adjusted front alignment but doesn't want to touch the rear one as it's "not adjustable". RR toe is -0.23 and it should be 0.10-0.20. LR is fine. Total rear toe is -0.05 and it should be 0.20-0.60.
The questions for you: would procedure and parts for Corolla be similar to Prius? What is the difficulty of this? Why total toe for rear wheels should not be close to zero (like the front wheels)?

 

For those who ordered the NAPA shims, did they come as a pair, or only one side?

 

Only one side and not in a pair. I'm still debating if I will use it. It has better instructions than the SPC.
Also, I still have the SPC shims as well.

 

I just had my car aligned and my rear shows slightly out of spec per their machine. However, it looks to be within spec per the an earlier thread post. What are your thoughts on my measurements? Should I adjust or leave as is?

Camber (Spec -2.0 to -1.0?)
LR = -1.2
RR = -1.4

Toe (Spec -0.3 to -0.28?)
LR = +0.05
RR = -0.05
Total = -0.01 (Spec -0.05 to 0.55?)

Thrust angle: 0.10​

 

subscribed... will be back when i'm due for alignment...

 

I know I'm necro-posting, and I apologize. I just wanted to chime in here for future readers to say that I have now also done this, using the NAPA part (I actually used a Moog part #, which was a lot easier to find in some places. It's Moog K66601). I was able to find it in stock at Amazon, RockAuto, and AdvanceAuto.

Somewhere else I read someone suggesting to drill the bolt holes instead of snapping out the tabs. I tried this, and ended up breaking my first shim because the drill bit bound on the plastic shim. This was even after I drilled a pilot hole. I recommend just snapping out the tabs as per the instructions.

I had a rough time getting the hubs/bearing assemblies out until I found this other post on PriusChat, which provided a trick that worked pretty well. Do NOT hammer on the back of the hub to force it out from behind if your bearing is in good shape and you plan on putting it back on - I punched a hole in the back of one of my hubs, and had to replace it at a cost of >$100.

I was able to torque the hub assembly bolts all the way to 66 ft*lbs without any problem.

Prior to installing these, I was at -0.32 and -0.35 on the rear alignment toe, so putting exactly 0.25 of toe on both sides should bring it back almost exactly to 'perfect'. However, I still haven't been able to take the car to an alignment shop to have everything checked, so I'll update this post once I've done that. Fingers crossed...

 

That's one of the biggest challenges; there just isn't any obvious way to get these hubs out but keep them suitable for reuse, and the method in that other post won't cut it either. That ends up putting the force on the inner, rotating part, through the inner race and balls of the bearing, against the outer ring to pull the hub out of the axle flange. It's no problem if your purpose is to replace the hub, but you canna do that to a bearing you mean to reuse—down the road, it's going to fail.



What's needed is a way to apply pulling force right at the flange that bolts to the axle. If I remember right, Gen 1 Prius had the threaded holes in the hub itself (bolts came through from the axle side), which might offer a way to do that, but I'm pretty much out of ideas when the bolts go through from the hub side so the holes in the hub have no threads....

-Chap

 

I agree - this approach isn't ideal. But yeah, in the absence of threaded holes in the hub, I can't really think of a better way to do this. I do think that the constant, slowly increasing transverse load is at least significantly better than the 'striking with hammer' approach, which applies unknown shock forces and seems to me far more likely to damage the bearing.

 

I can see how it could seem better, and maybe it is somewhat better, I don't know, but it still counts as pressing the bearing with the press force applied to the wrong ring, and bearing manufacturers definitely call that a no-no leading to later failure of the bearing. Now, how many miles later? That I can't say.

In another thread, somebody suggested maybe trying to get under the mounting flange/base with an air chisel, which might work maybe. Even getting it to turn a little, so the holes don't line up, might allow it to be pressed out by rethreading the mounting bolts through the axle flange from behind. I'm not sure how long a sustained vibration you need before risking "false brinelling", another condition that leads to eventual failure. It might be helpful to now and then spin the hub while trying to buzz it loose—false brinelling seems most likely when the bearing isn't rotating and grease gets shaken out of the ball contact patches.

The only foolproof approach seems to be to time your shim adjustments to be done when you're already planning to replace the bearing....

-Chap

 

I purchased the moog k6660-1 shim based on the advice further up in the thread, but I am really not understanding the instructions. I don't have alignment values for my car yet, but I wanted to make sure I understood what to do with trimming the shims once I do get it aligned. I have attached scans of the instructions to this message, if anyone could take a look and help me understand I would appreciate it. I think the main difficulty I'm having is understanding what they mean by the bigger bolder numbers in the upper lefthand corner, numbers 1-6, I don't see those numbers anywhere on my shim or on the template to potentially align with the shim. Also there seems to be a bit of a contradiction in their literature with the list indicating to use template S for a gen 3 prius, and the template itself indicating to use template Q. Any help would be greatly appreciated.

Edited to add that Moog has
K6660-1
K6660-2
K6660-3
K6660-4

Which I'm sure offer different thicknesses / degrees of correction, but hell if I can figure out what's what on moogs website