CK5
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71 K5 with a Cummins

:thinking: There is a CUCV hydroboost down in the shed... wonder if that would work.

The only issue I have with this plan is that it will add some twist into getting parts. The majority of the parts have all been 93 Dodge. If not that then the 71 K5. If there are brakes out of an 86 CUCV, it may be an issue down the road as far keeping track of what parts are from what. I guess the keep it simple (KISS) plan went up in smoke when the Cummins went in :weapon9:.


My truck is a hodge-Podge of all sorts of parts... Ford, Chevy, Mercedes-Benz, etc. :whistle:

Don't sweat it....just keep good records of the part numbers and/or vehicles that the parts came from and build a "master list" for yourself. Keep one in your glovebox, and one in a safe place at home. If you ever need a part, just refer back to the sheets....

As Luke said, use what works best. :waytogo:


-G
 
it will. I believe Z pulled his hydroboost from a mid-80's CUCV as well.

Yep, my hydroboost and axles were from an 85 cucv. Do it and don't look back. My truck stops on a dime now and I'm on 40's.

And like Greg said, just make a list. I've got stuff from 3 different era Chevy trucks, camaro, and loads of custom stuff on mine.
 
:thinking: There is a CUCV hydroboost down in the shed... wonder if that would work.

The only issue I have with this plan is that it will add some twist into getting parts. The majority of the parts have all been 93 Dodge. If not that then the 71 K5. If there are brakes out of an 86 CUCV, it may be an issue down the road as far keeping track of what parts are from what. I guess the keep it simple (KISS) plan went up in smoke when the Cummins went in :weapon9:.

I think my simplicity went away when I put Peterbilt, Freightliner and International truck parts on mine....
Just keep track of the donors/numbers and if it is a common part (like a drive belt) that is odd, keep a spare with you.
 
The CUCV hydro boost should go in just for the sake of my screen name :D.

Just to hit this from another angle, how will this affect the possibility of using hydro assist steering later? Will the K5 even need hydro assist? The plan is to have 35s with backspacing similar to H2 wheels. IIRC, hydro assist and hydro boost working together have specific needs in order to work right. I think it has something to do with having a pump that will handle a lot of flow/pressure and then have the ability to keep it cool.
 
if the biggest tires you plan on running are 35's, I don't see why you'd need hydro assist steering. I've been running 35's for years and never had an issue.
 
That solves the hydro assist issue. I think I will take you up on getting that measurement from the firewall to the end of the master cylinder on the hydro boost brakes. It should be interesting to see what the difference in measurements is.
 
Mc_measure.jpg

right behind the tape there is a little spot on the MC that sticks out a bit more so it's closer to 14 3/4".

How does that compare to the stock one?
 
The current brakes measure 15 1/2". 3/4" seems like it should be enough clearance.
 
The current brakes measure 15 1/2". 3/4" seems like it should be enough clearance.
attachment.php

looking at this pic your MC is square in front while mine is rounded. You could probably gain a bit more clearance in the critical spot by switching to a different type too. I believe mine is the stock MC for a 3/4 ton '72.

I think you're going to be happy you went with hydroboost especially with a diesel engine. :thumb:
 
Yes it was mentioned.already, and I wouldn't really want my brakes relying on that ****ty little pump.
 
Yes it was mentioned.already, and I wouldn't really want my brakes relying on that ****ty little pump.

Seems to work just fine on 10 of 1000's of Cummins equipped trucks running millions and millions of miles hauling heavy loads :confused::confused:
 
Seems to work just fine on 10 of 1000's of Cummins equipped trucks running millions and millions of miles hauling heavy loads :confused::confused:

I've owned a few first gen Dodges and the brakes reallllllly do suck and can be dangerous towing if not perfect. My new to me F350 idi diesel is not hydro boost and seems to be way better than the Dodge brakes but I still plan on switching them.
 
Looks like cummins vac booster was dropped for hydro boost in around 1996. That vacuum pump only runs the cruise control pod and the HVAC controls after that. As far as I know that's it. Seems like they learned something.
 
Looks like cummins vac booster was dropped for hydro boost in around 1996. That vacuum pump only runs the cruise control pod and the HVAC controls after that. As far as I know that's it. Seems like they learned something.

Mines a 97 and has Vacuum boosted brakes :dunno:

cummins.jpg
 
I had a 94 and a 95 with vac booster and a 97 and 98 with hydro booster. I just split the difference.

What you say is just fine, I.call bearly adequate. Perspective makes similar things different to different people. The ram guys upgrading their rear brake drum cylinders to GM rear drum cylinders didn't come about by accident. It's cause ram brakes traditionally sucked.

Regardless of what year it actually happened. vac boosters don't exist on any diesel pickups anymore because the fact is they're inferior to hydro boost.
 
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