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Discussion Starter · #1 ·
D.I.Y. Wheel Bolt Torque Tension.
Here is where we are treading on soft ground
The owners Manual for the Mazda C X30 states :-

Torque Values
108-147N.m
12-14 Kgf.m
and
80-108 ft pounds.

First of all, i am not in favour of hand held electric torque wrenches quick fix tools.
May I recomend that a certified Mazda mechanic check your wheel bolt torque values , do not leave this to chance.

A properly calibrated torque wrench would be my choice every time,.

There is a recomended bolt order pattern for re ~ setting wheel bolts.

Let me deal with the easy one first 80-108 ft pounds .

[1] I see several areas where there could be D.I.Y. problems.
Say , if the wheels have not been rotated on a regular basis .

[2] The application of "Copper Slip" or as such anti seize is not recomended there is no harm in wire brushing the threads of the wheel bolts.

[3] Bolt seizure preventing the D.I.Y. from changing out a flat will be dificlult, or virtually imposible.

Now we are faces with varable choices :-

108 ft pounds bolt torque is applied to cars which travel a high speed.
The lower limit of 80 ft pounds is reasonable for surban or in town driving.

Then again the average of 94 ft pounds could be considdered satisfactory for general driving.

Never the less .Wheel Bolt removal at these values will be dificult with out the aid of a beaker bar.

Driving speeds for "spare wheels "should be no higher than that shown in the owners manual.

" Mans worst enemy is dirt ".
 

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'21 GS awd
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Jeez. I have been driving and mechanicing on cars since I was 14 which is 59 years ago. I have changed countless wheels and never torqued a wheel.
You probably have a feel for what ~100 ft-lbs feels like, but not everyone does. A torque wrench takes the guess work out of it, and having properly torqued wheels is absolutely critical. Over torquing can stretch threads, which is just as bad as under tightened lugs.

I use a simple beam style torque wrench for wheels. Super cheap, and accurate enough for wheels.
 

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Discussion Starter · #4 ·
Jeez. I have been driving and mechanicing on cars since I was 14 which is 59 years ago. I have changed countless wheels and never torqued a wheel.
TORQUE WRENCH: D.I.Y.
The Mazda owners manuals in my opinion are the most comprehensive and best I have seen of all the car I have previousely owned.

Hand torquing a spare wheel bolts on a spare, while is acceptable under the circumstances say " out in the field " with car hand tools for get home driving ,speeds , should be some what reduced. The manual makes it very clear that using a proper torque wrench is required for standard wheel instalations.

May i thank you for your comment , however at the same time may i say that it is not good practice to sent simply the wrong message.

There are many references in the owners manual refering owners to seek the advice and services of a trained Mazda mechanic.
 

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2021 CX-30 2.5L AWD Pearl White
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Jeez. I have been driving and mechanicing on cars since I was 14 which is 59 years ago. I have changed countless wheels and never torqued a wheel.
As a professional technician (45 years), and an instructor we stress properly hand torqueing every fastener, especially wheels. Tights right, too tights broke.
 

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Discussion Starter · #6 ·
As a professional technician (45 years), and an instructor we stress properly hand torqueing every fastener, especially wheels. Tights right, too tights broke.
LOOSE FRONT WHEEL. : D.I.Y.
RE ~ ataching the front wheel on my Rav 4 .
I lowered the car to the ground more than enough the give bite to the tire in order to tension the wheel bolts.

I was able to secure the wheel bolts to my satisfaction, all seemed well, until i drove the car and found and heard that the wheel was loose.
Unfortunately the tire did not center verticaly when torquing down the bolts.
What had happened there the tire had forced the wheel off virtical center.

In other words I lowered the vehicle way too far.

Here is the cure ,only lower the vehicle sufficiently to prevant rotation on the wheel, or the parking brake and gear box should do the trick.

Aditionaly, dont forget to place the gear box in park and also apply the parking break to prevent "role off " due to un even ground.

DIY can result in unfortunate situations don't be timid . Ask for help!


WARNING .
Some spare wheels are very heavy and can cause personal injury.
 

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2021 CX-30 2.5L AWD Pearl White
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These lessons are often learned the hard way, hopefully with no damage done. A similar common trap for anyone DIY or a professional is the corrosion that can develop on a wheel and hub. It can cause the wheel to fail to seat correctly and the lugs will achieve torque, although if attentive you notice the rotation of the lug from snug until torqued is excessive. Then once driving the wheel breaks through the corrosion and now it's loose.
 

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Discussion Starter · #8 ·
These lessons are often learned the hard way, hopefully with no damage done. A similar common trap for anyone DIY or a professional is the corrosion that can develop on a wheel and hub. It can cause the wheel to fail to seat correctly and the lugs will achieve torque, although if attentive you notice the rotation of the lug from snug until torqued is excessive. Then once driving the wheel breaks through the corrosion and now it's loose.
I wonder how many people keep a flat spare wheel tire in the boot ?

Replacing and driving with the spare donut on the front steering position is considdered dangerouse .
It is safer to drive a car with the donut located at the the rear position.

The best course of action is well worth it by switching wheels, using two standard wheels for steering :-

[1] Remove the "curb side" back wheel and put it to one side.
[2] Attach the donut to the back wheel position " curb side" only
[3] Remove flat front wheel and place it in the boot.
[4] Install rear wheel as in [1] atach to the front wheel hub.
 

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2021 CX-30 2.5L AWD Pearl White
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I'm with Rdrokit. 58 years hand torquing cars, trucks, trailers, etc. Never once a problem.
I'm a firm believer in practice and establishment of strong repeatable routines when doing any service work. There are many who can say they have never had a problem doing any number of things. The question that must be asked is whether this a measure of competence at the task or is it just that there aren't enough exposure events yet. IMO, given enough chances and variations in circumstances even the most experienced person can make the simplest mistake. The most important thing then is to understand why it happened and what can be learned from it so that maybe it can be prevented from happening again.
 

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2021 PGM PP Turbo
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Actually, I consider myself very competent, John. If you still aren't sure about yourself yet, then by all means, keep practicing. No one's stopping you.
 
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