Proper Way of Measuring Rake

[304290]

I've had my 2019 ram for a few years now and with 41000 miles, thought it was a good time to replace/upgrade my tires. I just ordered a set of 285/65/r20 toyo open country at3 and was trying to decided which leveling kit I needed to go with. So I know most measure from ground to the center bottom of the fender. With that in mind, I get 36.75 on front and 38.5 on rears. So 1.75 on the rake. Simple right?

Well maybe not. I remember reading somewhere, that's not really accurate. The fender height is different on front to back, you should subtract that difference from the total rake. So I meaured the distance from the top of the tires to the fender and it's 6.5 inches on the fron and 8 on the back. So that would come out to being only .25 inches of rake? There was nothing inside or on back of the truck. and it was consistant on all four wheels. So if that's correct, then maybe something is going on with my suspension on the back? It's my understanding that these come with about 1.75-2.50 etc of rake from the factory. Or is it, I just just go by the measurment from ground to bottom of fender and disregard the fender height differences from front to back.

Now just a little more info about my truck. No air suspension, stock wheels and tires 275/55/r20, and no orp.

 

[HSKR R/T]

I've had my 2019 ram for a few years now and with 41000 miles, thought it was a good time to replace/upgrade my tires. I just ordered a set of 285/65/r20 toyo open country at3 and was trying to decided which leveling kit I needed to go with. So I know most measure from ground to the center bottom of the fender. With that in mind, I get 36.75 on front and 38.5 on rears. So 1.75 on the rake. Simple right?

Well maybe not. I remember reading somewhere, that's not really accurate. The fender height is different on front to back, you should subtract that difference from the total rake. So I meaured the distance from the top of the tires to the fender and it's 6.5 inches on the fron and 8 on the back. So that would come out to being only .25 inches of rake? There was nothing inside or on back of the truck. and it was consistant on all four wheels. So if that's correct, then maybe something is going on with my suspension on the back? It's my understanding that these come with about 1.75-2.50 etc of rake from the factory. Or is it, I just just go by the measurment from ground to bottom of fender and disregard the fender height differences from front to back.

Now just a little more info about my truck. No air suspension, stock wheels and tires 275/55/r20, and no orp.

No need to subtract anything from either measurement.

 

[304290]

That’s what makes sense to me. Just wanted to be sure. Thanks!

 

[Jimmy07]

I remember reading somewhere, that's not really accurate. The fender height is different on front to back, you should subtract that difference from the total rake.

This is true. The wheel well openings are different dimensions for the fronts vs the rears. That means that ANY measurement you take that involves the wheel well openings relating to rake would be inaccurate.
To get the true rake, you would take the longest, straightest run of body line, project that line past the front and rear wheels (using a string line or rotary laser), and measure from that line to the center of the front and rear wheel hubs, and the difference will be the rake.
In the photo below, I set the straight arrow across the bottom of the door jam body line, through the wheels. You can see the difference in height where the line goes across the center of the wheel hubs:

 

[304290]

Umm, interesting. I will do just that. You can go wrong with that method. Then I can compare with the other method to see just how accurate (or inaccurate) it really is.