Convert master cylinder to dual reservoir unit

[plabisso]

Hi All,

I'm a new member as of tonight along with my recent (February 2014) purchase of a one-owner 1966 D200 Crew Cab, 8 ft box, 318 V8, automatic and 63,000 actual miles. The master cylinder needs to be replaced so I thought this would be a good time to convert to a dual reservoir. Has anyone done this conversion and is there a model year master cylinder I could purchase that would closely match the bolt hole pattern from the original single reservoir or will I need to modify and drill new holes in the firewall to mount it? Any other tips/information would also be appreciated.

Thanks to all that can help me out! My truck will require lot's of wrenching to bring it back to it's earlier days so I will have lots of questions over the months/years ahead!

Paul
Milwaukee, WI

[Txas2step]

.Check this out in the Tech section. Should work with drums all around.

download/file.php?id=17269&mode=view

[BigG]

Did you use a proportioning valve? I did this conversion and have very little pedal, can anyone help. ( all drums, no booster, two split lines , nothing else) am I missing something? Thanks for the help BigG

[Hobcobble]

Hi All,

I'm a new member as of tonight along with my recent (February 2014) purchase of a one-owner 1966 D200 Crew Cab, 8 ft box, 318 V8, automatic and 63,000 actual miles. The master cylinder needs to be replaced so I thought this would be a good time to convert to a dual reservoir. Has anyone done this conversion and is there a model year master cylinder I could purchase that would closely match the bolt hole pattern from the original single reservoir or will I need to modify and drill new holes in the firewall to mount it? Any other tips/information would also be appreciated.

Thanks to all that can help me out! My truck will require lot's of wrenching to bring it back to it's earlier days so I will have lots of questions over the months/years ahead!

Paul
Milwaukee, WI

Welcome Paul.
The '67 & later 200 Series brake master cylinders would be dual reservoir. They
are a two bolt design. You would want to find a parts truck or someone
with one to harvest the firewall plate from. Secondly, there is a line junction
block located on the inner frame rail near the steering gear box. You'd want
to get one of these also. From there, it is a matter of plumbing in your new
lines/fittings. I'm sure others will chime in on this as well.
John

[Txas2step]

The 1972 d100 disc/drum MC shown in the thread I listed, appears to be a 4 bolt set not requiring an adaptor plate.

[Hobcobble]

The 1972 d100 disc/drum MC shown in the thread I listed, appears to be a 4 bolt set not requiring an adaptor plate.

I'm not positive of the bore diameter on that vs the 3/4T MC....
John

[kurt]

I have a 1965 or 66 Crew Cab. I have never been sure of the year. It had a single pot four bolt master cylinder. I coverted to front disks and used this

1972 Dodge/Ram Truck D200 2WD 5.9L 2BL 8cyl disc/drum
Autozone Part Number: 50-3122
Alternate Part Number: 62-3069 Cardone

It is a 4 bolt boosted disc/drum. You can also get it in drum/drum configuration. To use it I had to drill two more holes in the firewall for the 2 extra bolts and open up the center hole a little on the bottom side. I seem to remeber it hooked to my brake pedal with no issues. The extra holes in the firewall are probably because its boosted versus no booster. You might want to check the hole spacing on the two.

Booster hole.JPG (12.95 KiB) Viewed 1359 times

[Hobcobble]

Fire Wall Plate For Two Bolt Master Cylinder

Here's the plate for the '67 and '68 two bolt dual
reservoir master cylinder.
John

[plabisso]

I really appreciate everyone's input. I bought a MS for a '72 D100 & the bore size is 1 1/32" & I need 1 1/8" so that the plunger on the truck will fit in the end of the M/S. Either the master cylinders that I was able to find at local auto parts stores are 2 bolt design with 1 1/8" bore or 4 bolt with 1 1/32". I can't seem to locate a dual reservoir, 4 bolt with the larger 1 1/8" bore. It seems my options are to exchange the MS from the '72 D100 for an original single reservoir MC for my 1965 D200 & just not convert to a dual reservoir, locate a smaller diameter plunger that will fit the '72 D100 MS or locate a firewall plate off a '67 or '68 D200. Does anyone have any other suggestions or do you have a firewall plate I could purchase or know where I could get one? Any help would be appreciated!

PS I used the VIN look up feature on the Sweptline site & to my surprise, found out my D200 is actually a 1965! The title says 1966 so I don't know what happen between the original owner, the Illinois car dealership where he purchased the truck new & the Illinois and/or Wisconsin DMV 4 to 5 decades ago. I also have the 4 headlight front grill set up & learned on this site it was discontinued mid-model year in 1965 when Dodge went to the 2 headlight design so my truck must be a 1965 based on all this information.

Paul