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I'm destined for brake work in my near future and want to upgrade the M/C to a dual chamber while I'm at it. i like the idea of the pedal keeping pressure if i ever get a hole or rip a line off while off road. ive heard there was a master cylinder that was a direct replacement from an early 70's pick up but i cant recall the make or model. does anyone know anything about this?

also i know i will have to re-run brake lines as well. are there any pre-bent kits out there? what about the kits available through vintage power wagons?
http://www.vintagepowerwagons.com/pdf/p ... brakes.pdf
or would this be a waste of money if using the dual chamber M/C...


any tips, tricks, thoughts, woes, warnings etc. would be great.

thanks.

One option for the master cylinder is discussed here:

http://www.uglytruckling.com/M37%20Truc ... 20kits.htm

There may be others and Charles of M Series Rebuild now has a disc kit available. For the brake lines, you could make your own, buy a ready made kit from one of the vendors or purchase pre made lengths and build it up with them. I don't have the list of lengths but maybe somebody on here can post that if its available. I bought my own tubing, fittings and a double flare tool and after some practise did my own as good as any you can buy. The 1/4 tube and fittings are generally available or from the usual sources like Midwest Military or VPW. If you have a good auto parts place locally, they can help with all of it. Stainless tubing is a bit more difficult to flare, but with practise can be done. Doing it yourself is the fun of it for many of us.

Jess

I am looking to do the same project. The ugly truckling articles have been bookmarked for a while and are a great guide. I have been interested in these brake lines, http://store.fedhillusa.com, and I might buy their crimper also.

If one does the master cylinder conversion from the Ugly Truckling link, have you installed a residual pressure valve, or just split the single circuit into two and not worry about it? I ask since my truck skids the rear easily on braking, but I have not inspected or replaced anything.

ZGjethro wrote: I ask since my truck skids the rear easily on braking, but I have not inspected or replaced anything.

That would suggest you have a serious brake issue that needs to be attended to, being light in the rear end M37's are prone to the rears locking a bit but if it's locking the rears well before the fronts seem to be working then do a tear down and check for leaks, damaged shoes, broken springs etc. It's better to do it now than after having a crash and thinking to yourself "I should've done that". If you are not confident on brakes, get en experienced buddy or mechanic to help

MM

It brakes pretty well on pavement. However, on dirt or icy roads, it skids the rear pretty easily on harder braking. It seems out of balance compared to almost any vehicle I have driven. Too much bias to the rear, which leads me to believe the front brakes are not up to par. I can do anything I decide to tackle, and this question was about a proportioning valve, or residual pressure valve. Any info on those components would be appreciated

Sorry, I misread your threads intent.....
All M37 drum brake systems have the residual pressure valve, it should be in the front of your master cylinder as mine was, Once you fit front discs I think you have to remove it, I fitted discs to all 4 corners and definently had to remove it as it was keeping them lightly applied. A proportioning valve should not be required for a well serviced M37 brake system (although with no load in the back they can still get a little touchy, typical of any pickup), on my truck however it could now use one but I intend to split the system with the dual circuit master cylinder Brigand sent me and use the booster only on the front circuit and that should give the desired effect. On a side note, my booster is an old VH-80, would anyone have a parts diagram or even better, a service guide for one?
Thanks

MM

Thanks MM. I didn't know my stock master cylinder had a residual pressure valve. I am looking to redo my brakes and convert to the dual circuit MC as the Ugly Truckling link shows. I am guessing I'd need a residual pressure valve for the front and back circuits.

i wwas thinking of getting this mc. http://www.ebay.com/itm/131128264041?_t ... EBIDX%3AIT

Are there any two circuit master cylinders out there which might have a remote reservoir, or a cylindrical fitting which makes pressure bleeding easy? On my stock MC the fitting on top of the cover makes a great pressure bleeding connection

great info thanks for the information and links! looking forward to wrenching once the weather straightens up! i am not wanting to upgrade to discs, although they would be nice, i don't want to sink that much $ into the stock axles. i was more interested in upgrading just the master cylinder so i could have a safety net if one brake line gets a hole in it...the proportioning valve seems like an issue though.

I have done the MC upgrade to a DC master cylinder , I used the Uglytrucking upgrade , replacing the original MC with a dual circuit MC and I can tell you that just doing that made a huge difference in the stock brake system without spending a huge amount of money , as I've all ready empty my bank account several times with my M37 and its still not where I want it to be ........