The Stovebolt Site Forums The Shop Area Driveline Rear wheel cylinder fit

I’m installing new brakes on my 57 Chevy NAPCO project. On the rear backing plates there is a steel piece that appears to work as a retainer for the wheel cylinder boots. The replacement W/Cs are too wide by almost 1/2” so they don’t fit between the part on the backing plate. The new part #s are Carquest EW 13387 and EW 13388. I have a couple of old Delco cylinders with a casting # of 5450629 that are the right width, about 3”, but they are too far gone to rebuild. I’ve replaced the brakes on several Task Force trucks, but I’ve never had this problem. Any thoughts?

Thank you,
LJ

I had a similar issue with my ‘52 3100. The new Delco wheel cylinders appeared too wide to fit between the brackets that stop the pistons from over extending stopped the new cylinder from seating properly. It wasn’t until I realized that I needed to compress the pistons and boots that it fit. Tight but it did fit and they work properly. I hope this helps.

Thank you. I just finished looking at 40 pages of posts and found two that talked about this subject. I think one was yours. I’ll try pushing the pistons and report back. I was thinking that the body of the cylinder was too wide.

Larry

The ends of the pistons are likely extended outside of the bores. You can't see this because the boots hide them. To verify the fit you can mock up the cylinders without the rubber boots on. That way you will see the over-extended piston cups.
When the piston cups are pushed in, and the rubber boots are on, you nearly have to almost ruin the rubber boots to get the cylinders into place.
Carl

I’m on my way out to my shop so I’ll take a look.

Thanks

I'm not going to say you have the wrong cylinders or if they are made wrong as it's possible that that is all that is available.
However, you could grind a small amount off of each side of the bracket to give some more clearance.
I worked in a brake shop in the early 60's. One of the "technicians" would use an air chisel and cut the tabs off to rebuild the cylinders. When I asked him about what he was doing he stated that it was easier than removing the cylinder and besides "Ford's never used them and they built millions of cars and he never saw a problem with them". It may not be the best way but it worked for him.
Fred

Thanks Fred. I didn’t make it out to the shop last night and now it’s snowing and blowing. Once I get my courage up I’ll go out and turn on the heat. It was 16 with -3 windchill this morning. I think with the info you guys have given me I can make it work. That air chisel approach sounds a little extreme, but time is money. In my case I have more time than money so I’ll probably do a little grinding.

Larry

Those tabs prevent shearing of the bolts which hold the wheel cylinders in place. They also prevent the casting from breaking where the threads pass through. This all comes into play during emergency stops.
Grind if you must. I don't know anyone who shares the road with you in Colorado, and I don't expect to be driving through there either...
It would be a better idea to discover what is actually causing the problem.
Have you searched any NAPCO forum sites? They should be able to help you.

Thank you Carl. You make a good point. I have some Rsybestos wheel cylinders on the way. The rear axle on a NAPCO is the same as on a stock Chevy. I don’t want to modify anything that could be dangerous to myself or others. So I’m patiently waiting for the new wheel cylinders. I did check the cylinders that I have and the boots will be crimped if I install them.

Thanks,
Larry

From what I can remember the P/N's you listed are the same as the last ones I installed on a TF truck. If the wheel cylinder castings are substantially longer they may cause other problems as well. There seems to be a lot of variations in the offshore parts that are available lately. I certainly don't advocate doing any dangerous modifications. Of the thousand or so brake jobs I have done I have found some real messes inside when the drums were removed. However, most users of Bendix brakes including Ford did not have the "safety" brackets as part of their backing plates. I never encountered any issues as a result of not having them.
Fred

I have cut many of them back when I had a shop. It does not cause any safety problem.

I found that Raybestos WC 13388 and WC 13387 fit the backing plate with very little compression of the w/c boots. UP 13388 and UP 13387 from Napa are identical. Both are made in China. I took them all apart, and they appear to be well made. We’ll see how they work,

Larry

1. You have posted the same number for each brand. They are all the same. They are the correct number for rear TF 1/2T.
2. The tabs that stick out are safety stops to keep the piston from coming out. The boot will nest around the stop.
3. The front number is 14493 and 14494.
4. Front is 1 1/8" bore, rear is 1" bore.

WC= Wheel Cylinder
UP= Ultra Premium
Prefix does not matter

Good find Larry!
Nothing like finally finding the correct parts.

Thanks for all of the suggestions. Here’s a picture of where I’m at.

Very nice. The "Tri Fives" are the best of the TF and the 57 is the best of the Tri Fives. Very valuable truck. What is the GVW on the data plate attached to the cab?

Thank you. It’s a conversion so 5000lbs.

No real change in value to a factory 4X4. I've had lots of TF's including 4X4. A few months ago I sold 6 "Napco" 1/2T wheels.

We’re they the 17.5” wheels? I’m committed to the 16” I had made, but had considered the 17.5s. Which NAPCO did you have? I’ve had a 58 GMC Carryall that was a factory NAPCO, and a 59 Chevy NAPCO pickup. This 57 I’ve had for 36 years so it’s a keeper

Yes 17.5 x 5.25 Kelsey Hayes, 6 lug with clips. I had a 57 GMC Napco Carryall and a 56 GMC Carryall which I did a 4x4 swap from a 80's suburban. Then several panels and suburbans. Had a original 1957 Dairy Queen Panel also.
I just finished a 1960 GMC short wideside big window factory 4X4 with a 305 V6. All original except power steering, steel bed and wind up spare.
Regarding TF: I only did panels and suburbans. Then: Many other makes and models. All pre 73. In the 4X4 catagory: Land Rover, Nissan Patrol, Scout, Land Cruiser, Blazer, Willys panel...Next is a 57 Willys Truck.
I don't "restore" most, just refurbish and "conserve".

That’s a cool history. Lots of trucks that I would be happy to own as well. The NAPCO Suburban/ Carryall is my favorite. Well...back to work on the rig.

Larry