Which is better? NOS or Modified?

[fng]

My question is about brake wheel cylinders? While I'm doing the brakes completely I was thinking I might as well go ahead and do the Wheel Cyls too.
I was wondering whether or not to get some NOS or try to locate and fab some newer civvie stuff? Any body got experience with both ways?

[rpgdeity]

I'm not sure what is better, although I don't like the idea of using NOS stuff like wheel cylinders that have been sitting on a shelf for 40 years. Go down to NAPA and pick up some new ones. I keep hearing that the only modification you have to do is to file open the mounting holes just a bit. For whatever reason, I did not have to do this when I installed my wheel cylinders. No modification at all was needed. Here are the prt#'s:

Drivers side - 37263
Pass. side - 37262

They were $17.87 when I got them at NAPA only a few months ago.

[FSJGuy]

I agree. I'd get the new civvy ones unless you're looking for a true restoration for points in contests and such.

[Barrman]

I have run both on my truck. I couldn't tell a difference in performance when I switched all four at the same time.

Remember, these are drum brakes so performance isn't going to be all that great no matter what you do.

If you have a brake hone and access to new cups. You can probably rebuild your stock ones to work as good as anything you can buy new. All for around $4.00 per wheel.

I switched because they came on a set of extra axles I bought and I wanted to see if there was a difference. There wasn't.

[k8icu]

Most Mill parts for the most part have come from a civy application espically in these trucks so you should be able to get orginal new manufactured cylinders for the wheels. I think rpg has the stock part from napa right there. As for modified are there larger bore size cylinders that could be used to help increase stopping power? If that is an option then maybe go with that to give you just a squeek more stopping power.

[Kaiserjeeps]

Would a larger bore size require more pedal pressure to do the same work? This is a gray area for me. I need to read up on brake systems as I am having problems with my wagoneer.

[adk4x4]

The force (lbs) applied to the pedal is transformed to pressure (lbs/in^2) via the master cyclinder. If that remains the same, then an increase in bore size(more cup area seen by fluid) in the slave equal more force on the shoe. However, increase in bore = more fluid volume per travel of cups hence more travel of the master and thus pedal. Now the typical travel is minimal(if the brakes are properly adjusted) so a slight bore increase should not take too much pedal but provide some additional braking power.

For example, a 10% increase in bore size will provide 10% increase squared in cup surface area thus that much increase in shoe force per shoe.
However again, does such a part exist, can it be fit in the same spot.

It would be very interesting to see if someone could come up with a replacement part with a larger bore. In this case bigger is better if it fits.

[k8icu]

That's basically what I was asking....has someone come up with the part? Did Jeep use a bigger one on Civy trucks that might be adaptable?

[brute4c]

I dont know of a wheel cylinder with those criteria...that is NOT to say there isnt one...I have not done an exhaustive search for such a cylinder....

What I do want to add is that by using the modern Ford Van wheel cylinders, with the slight ovaling of the mounting bolt holes, one gets not only ne parts but stainless steel pistons...in our stock, vented to the air cleaner with a hose, brake systems that is a plus...corrosion resistance is a geat thing.

[5quarter]

Yup ford van cylinders work just dandy i replaced all 4 corners on mine