11" Brakes

I always assumed that I had 9" brakes and planned on upgrading to 11" and even found some backing plates finally. I measured the back of the backing plate yesterday and to my suprise they measure 11" in diameter. So now I'm thinking I have 10" brakes? Would this have possibly been stock on a 1970 CJ5 and is it really worth the cost and expense to upgrade to 11"? One more variable is that I REALLY want an emergency brake and I can do this if I replace the backs with the 11" backing plates I found. Would it be a bad idea to have 11" on the rears and 10" on the fronts or should I just replace them all?

 

Yes, a '70 should have 10" self-adjusting brakes.

 

I have found 11" brake backing plates to measure 12" across

 

Thanks for confirming that I have 10" is there enough performance advantage to justify swapping them from 10" to 11". The backs are a no brainer for me because of my desire for an emergency brake.

 

Then it's settled 11" all the way around.

 

We put 11" drums on just the front of my dad's otherwise stock 69, & it made a noticable improvement in stopping power.
When you say you want an e-brake, I'm assuming the stock one on the transfer case is gone?

 

You assume correctly it is gone and I am definitely going to upgrade everything to 11". The drums are currently on the donor and I don't have a gauge to measure them to make sure that I can have them turned any tricks or suggestions to help protect me?

 

Pull them and take them to your local shop - they will measure them.

If the yard won't throw them in for a cheap price (or free), just get new ones. $20 each from RockAuto, last I looked.