Community Forums

JoeSR · 03-23-2023, 05:54 PM

Per Workhorse, I have Bosh ZOH-T brake system on my MH. Per some on this forum, I should be lubing the caliper pins. This requires removing the two 18mm caliper bolts. The bolts are torqued to ~100 ft-lbs. A medium strength thread locker is also used.

The top caliper bolts on the rear wheels are directly opposite the leaf spring. There is just enough room to get a 3/8” drive socket and breaker bar in there. I can’t get enough torque applied to break the bolt loose.

How have you guys done this?

I have ordered a 3/8” drive 18mm torque adapter from Napa. I should be able to able to add a 3/8 to 1/2 adapter and then use a 1/2” breaker bar. I expect to break the torque adapter (3/8” drive sockets are good to a little more than 100 ft-lbs.).

I could use heat on the bolt to soften the thread locker, but that may damage the caliper pin silicon seal.

So, again what have you guys done?

The attached picture shows the right rear leaf spring and a 1/2" drive socket on the top caliper bolt.

MrMark52 · 03-23-2023, 07:02 PM

Watching.

edge68474 · 03-23-2023, 07:08 PM

Me too.

donr103 · 03-23-2023, 08:17 PM

Take your 18mm combo wrench to large hardware store.. get rectangular steel box tubing to fit it.. at home cut it to lengthy to fit... 2ft on box tubing at 50 pounds should be close..
Good luck and keep us posted

shootist · 03-23-2023, 08:28 PM

You can take the box end of a second long wrench and slip it over the open end of the wrench you have on the nut making it twice the length. I have half inch impact wobble sockets and an impact Gun to do what you are doing. Also have 18” long ratchet wrenches. A 100 lbs isn’t all that much in the scheme of things. Don’t be resorting to heat, these are your brakes. I must ask, are you trying to split the calipers or just take them off the rotor?

DR60 · 03-23-2023, 08:30 PM

When you raise the frame, and the suspension droops does this put the socket in a better place? DR

shootist · 03-23-2023, 08:36 PM

Here ya go

https://www.bing.com/videos/search?q...E9&FORM=WRVORC

edge68474 · 03-24-2023, 12:36 PM

Quote:

Originally Posted by shootist

Here ya go

https://www.bing.com/videos/search?q...E9&FORM=WRVORC

Yep. I do that at times. Sometimes I have to think and move the wrench around a bit till I get it right, lol.
That's a good one though and very useful. Thank you

yeloduster · 03-25-2023, 07:51 AM

I have Craftsman ratchets. I took my 3/8" drive socket, put my ratchet on the socket, put a cheater on the ratchet handle and took it off.

The ratchet is guaranteed for life, if I break it I take it to Lowes and get a new one no questions asked.

I have done similar things with my Craftsman ratchets for as long as I have owned them.

PS, I have NEVER broken a ratchet this was! I have broken sockets and socket extensions though.

JoeSR · 03-25-2023, 05:16 PM

All, thanks for the suggestions.

Using a cheater bar or a variant of that idea may win out. I have a 6 point 3/8” drive impact socket on order. With a little grinding to shorten it some, it should fit. That will put only the breaker bar at risk.

To get the spring out of the way I would need to remove the U bolts from the spring/axle. This would be a last resort.

Fortunately for the rest, the bottom rear caliper bolt and both front caliper bolts are easy access, easy enough to get the impact wrench on them.

MrMark52 · 03-26-2023, 07:51 AM

I’m inclined to say - I would think lifting the coach frame would allow the axle to drop enough to allow straight-on access to the bolt.

How else would one be able to torque it (if using assorted end wrenches)?

JoeSR · 03-26-2023, 08:47 AM

I was able to break loose that caliper bolt last night.

I found a 6pt 3/8 drive 18mm socket locally. With my angle grinder I reduced the length of the socket by ~0.1”. This gave me enough room to get my 3/8 drive breaker bar and socket on the caliper bolt, loosen it and then get the tool off again. I was forced to use a cheater pipe on the breaker bar.

When I am done cleaning and lubing the caliper parts, the bolt will get torqued using a torque adapter. See >> https://www.napaonline.com/en/p/CHTT...ressionRank=14

I added a different view of the set up below. From the top to the bottom you see the leaf spring, tool and the caliper. A tight fit.

LETMGROW · 04-02-2023, 06:47 AM

Quote:

Originally Posted by MrMark52

I’m inclined to say - I would think lifting the coach frame would allow the axle to drop enough to allow straight-on access to the bolt.

How else would one be able to torque it (if using assorted end wrenches)?

How would dropping the axle down help? The backing plate, caliper, rotor etc. are all attached to the axle. They will move with the axle.

MrMark52 · 04-02-2023, 07:26 AM

Quote:

Originally Posted by LETMGROW

How would dropping the axle down help? The backing plate, caliper, rotor etc. are all attached to the axle. They will move with the axle.

As the axle moves away from or closer to the chassis, the radius of the leaf spring changes (one end of the leaf is usually fixed while the other end floats).