My CUCV M1009 To be named later build

[underdrive]

I thought I would pull the motor when I was changing the tranny. Their would be next to nothing holding it in. At that point I can change seals check for crap in oil pan screen. I can also re-torque main caps. ( a week spot in the engine)

Ah, yes, if you have concerns about the main caps by all means tear into it. Good call on changing the seals and such as well.

I agree with everything your are saying. My problem is if I use an Eldorado caliper its about $20 extra each vs the $300 plus using the driveline brake. That $300 is a large down payment i can use for a winch, front bumper, or roof rack. I have not heard a strong argument from anyone for against putting the driveline brake close to the top of the list.

Driveline brakes are legit, most if not all medium-duty trucks with rear discs use them. Full aftermarket setup is expensive yes, but depending on your fab skills you may not have to buy a bolt-on kit. If you're stuck buying a premade kit, then yes, hard to justify it given price of Eldo calipers. However, as mentioned by the Hidesertwheelin, do look into availability of the brackets. And to be honest, the only reason I'm even entertaining the idea of conversion discs is because for a fullsize truck yours is fairly small and light, if that were a 3/4-ton or larger truck I'd say just keep the drums and possibly upgrade wheel cylinders to the 1-ton DRW size if possible (which it should be). Wait, didn't I already suggest that earlier? lol

 

[jackel44]

Driveline brakes are legit, most if not all medium-duty trucks with rear discs use them. Full aftermarket setup is expensive yes, but depending on your fab skills you may not have to buy a bolt-on kit. If you're stuck buying a premade kit, then yes, hard to justify it given price of Eldo calipers. However, as mentioned by the Hidesertwheelin, do look into availability of the brackets. And to be honest, the only reason I'm even entertaining the idea of conversion discs is because for a fullsize truck yours is fairly small and light, if that were a 3/4-ton or larger truck I'd say just keep the drums and possibly upgrade wheel cylinders to the 1-ton DRW size if possible (which it should be). Wait, didn't I already suggest that earlier? lol

what years should i look for a driveline brake?

 

[jackel44]

you are right that was from a 1979 CADILLAC ELDORADO 5.7L 350cid V8 : Brake/Wheel Hub : Caliper

 

[jackel44]

I guess I'm back to square one.

 

[hidesertwheelin]

I guess I'm back to square one.

Well depending on how fast you want to put disk on and if I can or cannot get them to work up to my standards on my heavy ol Suburban, I may have a entire set up for sale.

 

[jackel44]

Well depending on how fast you want to put disk on and if I can or cannot get them to work up to my standards on my heavy ol Suburban, I may have a entire set up for sale.

i was reading that its best to find a 14 bolt ff from a early 2000 and rob all the disk parts. That way you get a good e-brake and disk. You are right the Eldorado conversion is problematic, they are not self adjusting and prone to failure. The driveline brake cant be used for an emergency brake. I will make some calls and see if i can find the axle.

 

[underdrive]

IMHO driveline brakes are actually very effective as e-brakes, as any braking torque they produce is automatically multiplied by the ring and pinion ratio. If brake is attached to the transmission or transfer case then you are indeed at the mercy of the U-joint gods, however if it's on the axle itself then that problem goes bye-bye. Having said that, I would highly recommend you don't mess with any of that, and instead hold out for a factory drum-in-hat setup from the early 2000s models you mention - that stuff is engineered to stop and hold a truck much bigger than yours, and you won't have to venture into scary-fab land like you possibly would with any driveline brake. Considering the importance of brakes on any vehicle, and the liability for the OEMs if they don't design them right, I'd jump on any chance of using a factory system over something aftermarket. Exception would be if said aftermarket solution is actually better than factory, like with larger rotors and calipers, but that is not the case here. So yes, go for the OEM-disc axle if you can find one.

But on the other hand I kinda think you're overthinking this - hydroboosted factory 1-ton drums have little problem stopping a 10k truck, you're not gonna be anywhere near that heavy. So I don't see it as a very big deal if you run the 8-lug drums for a while till you source out the OEM discs. I'd say just focus on swapping axles and transmission in and doing the engine work and what not, you can put the discs on the back burner and I doubt you will miss them a lot if they don't happen before our trip.

 

[hidesertwheelin]

i was reading that its best to find a 14 bolt ff from a early 2000 and rob all the disk parts. That way you get a good e-brake and disk. You are right the Eldorado conversion is problematic, they are not self adjusting and prone to failure. The driveline brake cant be used for an emergency brake. I will make some calls and see if i can find the axle.

Are the factory 14-bolt disk w/ drum parking brake compatible with older 14-bolt axles? I didn't think they were, but I could be wrong.

 

[jackel44]

Are the factory 14-bolt disk w/ drum parking brake compatible with older 14-bolt axles? I didn't think they were, but I could be wrong.

The bearing size is the same, im checking on the other measurements.

 

[edlaffoon]

Can I offer some advice based on your list?

1. Roof rack. I haven’t decided if I want to run with my fiberglass shell or use my canvas one and make some removable sides.

-For a roof rack the topper will probably crack eventually if you drill it. If you go that route have a boat shop fiberglass some threaded inserts into the top, otherwise build a custom rack that goes around the sides. I have a TON of photos of these I could email you, but you can find then all on the web too.

2. Front bumper with winch

-Yes

3. Rear bumper for spare and fuel holder

-Yes. For the same reason as above. Some of us have more stuff to carry than others. There are 5 people in my K5, my kids can't sit on top of my spare, so at the moment I don't carry one. A rear carrier is in the works. Regardless keep in mind all of this added weight means an increased spring rate is on order too.

4. Larger stock fuel tank.

-Yes BUT this is difficult on the K5. A larger tank will hang 2-4" lower than stock (there is no room for the tank to move forward so to increase volume they only move down). I'd keep that in mind and be prepared for a new skid plate as well. Check the dimensions carefully before buying.

5. Manual transmission swap

-Yes. This is still on my list as well. If you can find a doner be sure and grab all the pedals, brackets and hardware.

6. ¾ ton axles mainly due to gear ratio.

-Yes although not required unless you plan on tires 35" or larger. You can always re-gear your current axles to save money. If you do plan on a swap pull the diff cover off the one you're going to buy and count the teeth to verify the gearing. There's a lot of "4.10s" out there that are not.

7. Custom awning for the rack while it is parked at camp.

-A good Idea. I'd like to see this.

8. Upgraded lighting.

-Yes. I can make some recommendations here too. PM me if you want. Basically LED everything.

9. While tranny is out to pull the motor and check mainbearing tolerances.

-Yes, this is an excellent practice while you're in the area.

10. Change oil pump

-Yes

11. New engine cross over bracket (more stronger, lighter, better hidden)

-I'm not sure on this one, more strength can't hurt though.

12. Disk brakes for rear

-I hate rear disks. When you go to 3/4 ton axles your braking issues should go away. Do that first before you decide.

13. New 4 wheel disk master cylinder

-See above. Plenty of options here to help with drums too.

14. Steering strengthening mod

-This should be at the top of your list in my opinion. This is a major weakness on these trucks that needs to be addressed as soon as possible, even for street driving.

Those are all opinions, based on some experience. Hope that helps.

 

[jackel44]

The bearing size is the same, im checking on the other measurements.

I pulled this from the ck5 K5DREAMER"Now, at this junkyard i couldnt find a FF axle (D60/D70/14bff) with disk brakes... however i found what i think is a 3/4 ton 14bsf axle with 8 lugs and the DIH disk brakes. It was marked as coming off of a 2000 GMC truck. I worked for a while, and managed to get one side kinda taken apart, but didnt have all the necessary tools to get it completely apart. and had a date at the shooting range so i had to leave.

Major points i noticed.

1. the rotors from the 3/4 ton axle do of course fit onto the FF hubs.
2. BUT the hubs are much thicker from the front surface to the back of the flange, which limits the depth the parking brake can get to.
3. On the 3/4 ton rotor, the depth of the parking brake drum is 3in. which matches the measurement from the WMS to the inner side of the parking brake shoe on the 3/4 ton axle.
4. the depth of the SRW hub is 2in, giving only 1in for the parking brake shoe to grab onto. the parking brake shoe is 1-3/4 inch wide. so that means about half the parking brake shoe would engage the rotor, meaning half the holding force of the factory setup.
5. the BIGGEST problem i see, is the mounting flanges for the two axles. the 1998 G-van drum axle has tiny mounting plates for the backing plates. using maybe 13mm or 15mm bolts to hold it on, and the flange is maybe 3/8in thick. The 2000 GMC truck axle has a HUGE mounting flange which uses big studs and 24mm nuts to hold the caliper bracket and parking brake parts onto the axle, and that flange was maybe 1/2-5/8in thick.

I obviously have no faith in tiny flange and bolts to hold what a huge flange and 24mm nuts held on. But I think A relatively skilled welder could weld the caliper bracket to the axle tube and solve the problem.

or an adapter plate of 1/2-5/8in billit could be made in a way that the center is "notched" or "hollowed out" so that the smaller flange fits inside of it snuggly, so any rotational force is not carried by the little bolts, and is transfered directly into the welded on flange. and the little bolts simply hold the adapter onto the flange. and then the caliper bracket mounts to the adaptor.

So in short, the disk brake setup from a 3/4 ton SF 14bff could work with some sort of adaptor, but it would be kinda half assed with that limited engagement of the parking brake shoes. "

I will put it in the back of my mind and move forward.

 

[jackel44]

I concur with member Underdrive's assesment of the priority list.

Extra fuel cans are a low priority as your truck has a large tank and gets nearly 20 mpg with the 6.2 diesel.

The rear disk brakes can wait : I have the corporate 14 bolt rear in my Blazer w/ drum brakes and they work very well in adverse conditions as is.

Spare carrier, well until you get bigger tires, there is a factory mount inside behind the flip/fold seat. When I went to 36" tires on humvee wheels, the spare lays flat (horizontal, not out of air ) behind the rear seat. When we go for the expedition look, we can get carried away with weight on the roof and weight behind the rear axle which will adversely affect performance.

You have the spin-on fuel filter and I think you said glowplug relay bypass, good reliabilty enhancing mods. Another peculiar characteristic of the CUCV is the headlight wiring. I have the auxiliary harness from LMC that solves the problem of operating the headlights plus heater blower on the same circuit.

A lesson I learned from member Joaquin Suave is to beware of "scope creep", that is, its tempting to make a long list of stuff to do and while you are at it do more stuff....the truck end up in the garage more than on the road.

Just sharing cuz I'm there, doing that

I already did the headlight mod but kept the facory headlights for now. I had really no choice my 30 amp fuse kept getting hot and melting.

 

[hidesertwheelin]

I pulled this from the ck5 K5DREAMER"Now, at this junkyard i couldnt find a FF axle (D60/D70/14bff) with disk brakes... however i found what i think is a 3/4 ton 14bsf axle with 8 lugs and the DIH disk brakes. It was marked as coming off of a 2000 GMC truck. I worked for a while, and managed to get one side kinda taken apart, but didnt have all the necessary tools to get it completely apart. and had a date at the shooting range so i had to leave.

Major points i noticed.

1. the rotors from the 3/4 ton axle do of course fit onto the FF hubs.
2. BUT the hubs are much thicker from the front surface to the back of the flange, which limits the depth the parking brake can get to.
3. On the 3/4 ton rotor, the depth of the parking brake drum is 3in. which matches the measurement from the WMS to the inner side of the parking brake shoe on the 3/4 ton axle.
4. the depth of the SRW hub is 2in, giving only 1in for the parking brake shoe to grab onto. the parking brake shoe is 1-3/4 inch wide. so that means about half the parking brake shoe would engage the rotor, meaning half the holding force of the factory setup.
5. the BIGGEST problem i see, is the mounting flanges for the two axles. the 1998 G-van drum axle has tiny mounting plates for the backing plates. using maybe 13mm or 15mm bolts to hold it on, and the flange is maybe 3/8in thick. The 2000 GMC truck axle has a HUGE mounting flange which uses big studs and 24mm nuts to hold the caliper bracket and parking brake parts onto the axle, and that flange was maybe 1/2-5/8in thick.

I obviously have no faith in tiny flange and bolts to hold what a huge flange and 24mm nuts held on. But I think A relatively skilled welder could weld the caliper bracket to the axle tube and solve the problem.

or an adapter plate of 1/2-5/8in billit could be made in a way that the center is "notched" or "hollowed out" so that the smaller flange fits inside of it snuggly, so any rotational force is not carried by the little bolts, and is transfered directly into the welded on flange. and the little bolts simply hold the adapter onto the flange. and then the caliper bracket mounts to the adaptor.

So in short, the disk brake setup from a 3/4 ton SF 14bff could work with some sort of adaptor, but it would be kinda half assed with that limited engagement of the parking brake shoes. "

I will put it in the back of my mind and move forward.

Do you have your 3/4 ton axles yet? If not, why not just get a complete newer AAM 11.5" rear with the factory disk brakes and install it?

 

[jackel44]

Can I offer some advice based on your list?

1. Roof rack. I haven’t decided if I want to run with my fiberglass shell or use my canvas one and make some removable sides.

-For a roof rack the topper will probably crack eventually if you drill it. If you go that route have a boat shop fiberglass some threaded inserts into the top, otherwise build a custom rack that goes around the sides. I have a TON of photos of these I could email you, but you can find then all on the web too.

2. Front bumper with winch

-Yes

3. Rear bumper for spare and fuel holder

-Yes. For the same reason as above. Some of us have more stuff to carry than others. There are 5 people in my K5, my kids can't sit on top of my spare, so at the moment I don't carry one. A rear carrier is in the works. Regardless keep in mind all of this added weight means an increased spring rate is on order too.

4. Larger stock fuel tank.

-Yes BUT this is difficult on the K5. A larger tank will hang 2-4" lower than stock (there is no room for the tank to move forward so to increase volume they only move down). I'd keep that in mind and be prepared for a new skid plate as well. Check the dimensions carefully before buying.

5. Manual transmission swap

-Yes. This is still on my list as well. If you can find a doner be sure and grab all the pedals, brackets and hardware.

6. ¾ ton axles mainly due to gear ratio.

-Yes although not required unless you plan on tires 35" or larger. You can always re-gear your current axles to save money. If you do plan on a swap pull the diff cover off the one you're going to buy and count the teeth to verify the gearing. There's a lot of "4.10s" out there that are not.

7. Custom awning for the rack while it is parked at camp.

-A good Idea. I'd like to see this.

8. Upgraded lighting.

-Yes. I can make some recommendations here too. PM me if you want. Basically LED everything.

9. While tranny is out to pull the motor and check mainbearing tolerances.

-Yes, this is an excellent practice while you're in the area.

10. Change oil pump

-Yes

11. New engine cross over bracket (more stronger, lighter, better hidden)

-I'm not sure on this one, more strength can't hurt though.

12. Disk brakes for rear

-I hate rear disks. When you go to 3/4 ton axles your braking issues should go away. Do that first before you decide.

13. New 4 wheel disk master cylinder

-See above. Plenty of options here to help with drums too.

14. Steering strengthening mod

-This should be at the top of your list in my opinion. This is a major weakness on these trucks that needs to be addressed as soon as possible, even for street driving.

Those are all opinions, based on some experience. Hope that helps.

I appreciate your input.
1. Roof rack: Space will be my biggest factor, with 2 adults and 3 children. I don’t like the thought of having a spare on the top, that’s why I wanted on the back. I know it would fit inside.
2. Front bumper: Nothing to add
3. Rear bumper I was also thinking on spare water can.
4. I think I’m going to scrap the larger fuel tank
5. Manual transmission. I have everything except to change the seals new clutch and flywheel
6. Yea I’m going from a 3:08 to a 4:10 I will probably running 33s
Final Gear Ratio : 4.10
Tire Size: 295-75-16
Max Power RPM: 2500
Limit RPM: 2800
********************************************
MPH RPM (in Gears)
*******************************
1 2 3 4
********************************************
5 1350 738 350 206
10 2700 1476 701 412
15 2214 1051 618
20 1402 824
25 1752 1031
30 2102 1237
35 2453 1443
40 2803 1649
45 1855
50 2061
55 2267
60 2473
65 2679
70 2885
7. Awning: I think it will be more like a tarp tied to the rack with 2 tent poll on each side.
8. Lighting: I’ll give you a shout
9. Motor: seal change If time permits
10. change oil pump: If time permits
11. Motor cross over bracket: defiantly the bottom of my list.
12. Disk brake I’m shelving this one for now. My drum set-up was a rotten mess so if I do drums I will have to buy a bunch of parts. I think I’m leaning on the plain calipers and line locks for now.
13. Master cylinder change: It would be an easy swap if I go the disk route
14. Steering strengthening mod: You are correct this is at the top of my list

 

[jackel44]

Do you have your 3/4 ton axles yet? If not, why not just get a complete newer AAM 11.5" rear with the factory disk brakes and install it?

I have the rear end already. I was reading about them today. Do they just drop in or do you have to move the brackets?