Prius Prime Plus in my hands

GOOD NEWS!!!

It is just the bumper cover. The TIS instructions look clear enough so all I have to do is probably remove the cover and reattach.

Oh BOY! I get to work on my new car! (I'm a Prius owner who rejoiced when the warranties ended and I felt free to do my own work.)

Bob Wilson

 

It turned out to be fairly easy but somehow, I didn't get all of the photos I thought I was taking. Regardless:

• one medium flat screwdriver
• one medium phillips screwdriver
• one 10mm socket and extension

Process:

1. On the side rear light at the top, there is a black cover that easily pries off with the flat. It snaps on and off, to expose the 10mm bolt.
2. Remove the phillips screw on that side and the 10mm bolt.
3. On the bottom by the wheel well, remove two pins using the flat.
4. Pull the bumper side a little to make sure it flexes.
5. Push the bottom facia up so it no longer blocks the bumper cover from movement.
6. Check the front side inner lip to make sure they aren't folded in: They can easily be bent as needed with the fingers. This bumper cover is remarkable.
7. Test to make sure the inner tab will fit into the black, plastic slots on the rear panel.
8. Use your hand to snap/fit the bumper cover into the slot:
9. Replace the two plastic pins by the rear wheel.
10. Replace the bolt, screw, and snap in the plastic cover.

It took me about 30-40 minutes because I had to figure out about straightening the inner tab. It was folded, probably from my earlier attempts, so it would not slide into the slot. If it doesn't work, pull it out, fix, and do it again. It will work.

So I presented myself with a bill for $342 and a note to update the car maintenance records and contact my insurance company. Since I have a $1,000 deductible, it will only update my driving record and increase future insurance premiums. Finally, I wrote a note to have the HSV police cite myself for reckless driving over a mailbox.

Bob Wilson

 

I bought a full-size spare and future tire for our Prime from Tire Rack:

• $74.00 (close out) - A8 15x6.5 wheel
• $96.25 - Ecopia EP422 Plus, 205/65/R15 tire (planned replacement for OEM)
• $195.18 - includes shipping . . . all new

When traveling with wife and dogs, I want to minimize the risk of a flat. I do have a puncture repair kit but I thought about 'a dark and stormy night.' ... No, I want to replace the flat and continue the trip.

I'll still have to pickup a jack and tire tool but don't see any particular problem. Once I have the spare, I'll measure the inside diameter and see if I can fit the jack inside along with a tire tool.

Bob Wilson

 

Ok, lug wrench?

Bob Wilson

 

Investigating tire tests using chalking the driver side, rear:

• No problem although tread #4 seems under applied.

The passenger side, rear:

• Inside tread carries too much load -> too much negative camber or possibly a toe out problem.

I need to replicate testing using my tire temperature scanner.

Bob Wilson

 

Tire temperature profiles:




I measured the passenger tire first which took about a minute. Then the driver side which also took a minute. The data suggests both tires have too much negative camber.

Bob Wilson

 

I prefer to take measurements and then adjust. Speculating on another car is not a good idea. But let me share how I took these measurements:

That is an IR thermometer mounted on a piece of shirt cardboard affixed to the three legs of a small tripod. The tripod holds an iPhone that is focused on the temperature display. That IR thermometer is put in continuous reading mode.

I drive the car ~10 miles at high speed and pull off the highway onto a parking lot. I then make a movie showing the tire tread temperature for each of the five treads. In my case, I did two passes on the passenger side and then two passes on the driver side.

IMHO, Toyota and BMW have too much negative camber on the tires. Worse, I can not depend on the service departments to change it to what I want. So I'll do it myself.

There are two approaches: (1) metal tabs, and (2) Specialty Products shim-disk. I used both on our 2003 Prius and found the metal tabs are much easier to install and can fix camber on one side and toe on the other. The Specialty Products shim-disk can handle both camber and toe on a wheel-by-wheel basis.

My thinking is to do the tabs for now. I live in an area with little snow and salted roads. Since I tried both, I'll probably go with the metal tabs for now.

One problem is I can't buy a life-time alignment from Firestone, yet. I haven't check Goodyear. However, it looks like I may be able to do my own camber and toe measurements. If I go with self-measurement, it will be a lot easier to measure and adjust.

UPDATE:

• TIS reports "rear camber can not be adjusted" -> by Toyota. I'll just have to do it myself.
• Before removal, I have to disconnect the 12V ground to 'safe' the brake system.
• I need a camber bubble gauge with magnetic base to do before and after metrics. This allows me to dial in the exact camber change.
• I'll probably have to remove the caliper assembly before unbolting the rear wheel mount. The trick is to do it without opening the flexible brake line hose and doing the parking brake.
• I'll probably use metal tabs to adjust camber on both sides. I suspect toe is OK.
• Repeat the temperature profile and hopefully, problem solved.

Bob Wilson

 

Gen 1 too and I used shims to adjust the rear toe and camber. But I used Firestone's "lifetime alignment" service to check what I'd done.

Specialty Products makes a nice one:

I started with metal tabs but later switched to these. I had occasion to take one off later hoping it had reduced the risk of rust only it didn't appear to work that way. I didn't have a rust problem, Alabama hasn't had salted roads but maybe twice in the past 10 years. So I'm planning to just use metal tabs.

Happily, this looks very familiar:


The axle and mount is just like our 03 and 10 Prius. However, there is a 'shield' which should minimize exposure to road wet. What I'll do is:

• disassemble to what you see and put the brake disk back on the axle, tight but not torqued
• measure the camber
• take the brake disk off
• loosen the four mounting bolts and pull it out enough to insert two shims on the top
• torque the bolts and put the brake disk back on
• measure the camber change -> looking to take it to -0.25 to 0.0
• repeat above until I get the camber I want
• reassemble

Then I'll do the same on the other side. The tricky part is there is a one-time use clip on the parking brake cable that I'll need to get.

I'm due for the 5k check in about 500 miles so I'll ask them to check the alignment. If I've done it right, they'll see nearly neutral rear wheel camber . . . which is not something Toyota volunteers to fix. <GRINS>

Since an alignment usually means fixing the front toe, I'm assuming the front camber is adjusted by using a camber bolt like the 03 and 10 used. Once I see the numbers, I'll order the right part and replace on my own.

I did but pretty colors don't give me numbers and they are a little pricy. My trick works good enough. Don't let perfect be the enemy of 'good enough.' <grins>

Bob Wilson

 

What clued me was the recent 4-wheel alignment of our BMW i3-REx. Then I noticed a lot of articles claiming a -1.0 degree camber is common to handle turning forces that try to 'roll' the tire. I also remembered the grief I had with the 03 and 10 Prius.

I want my tires to wear out on all tread grooves at the same time, not lose a tire because one side wore out too fast. This is why a good temperature map helps identify what is really going on.

Bob Wilson