Conversion issues, what to do next?

[NoDak]

Ok. If I understand this correctly.... and since I have the HB installed... really what I need to to is remove the '96 vintage MC and put the original '99 MC back in this hot rod.

Of course, same goes for anti-lock brake module... remove '96 vintage and put the '99 back in.

I'm not sure I recall seeing any left over push rod? But, if the pedal is in the right place now with the HB in place, the push rod we have in it is probably good to go!?

Shoot, this seems too darn easy. Should have asked a couple years ago, before we got started. Oh well, maybe others can learn from my mis-steps, eh?

 

[Burning oil]

Now your confusing me with what you have installed or not.
Basically you can run whatever MC, antilock you want. Just swap in the HB inplace of the vac booster, done.

 

[NoDak]

Yeah! I appologize for any confusion... but I could tell by your post(s) we were on different pages so to speak. But I'm fairly certain now that I'm straight on what I need to do.

For your sake and probably a few others, I'll recap what happened from the start;
1. I started with a prefectly good running 1999 5.7L gas Suburban 1500 6-bolt wheels (alias; project Suburban)
2. Then bought a "tree fell on it" 1996 6.5L Turbo Pickup 2500 8-bolt wheels (alias; donor truck)
3. Removed all gas related parts from Suburban and then went about making it a Diesel Suburban
4. Removed (un-wittingly) the originally equipped VB, MC and antilock brake module from 1999 Suburban (parts still in storage, luckily).
5. Installed HB, MC and antilock brake module from 1996 vintage donor truck, into the 1999 Suburban (should have only swapped HB for VB per your suggestion).

So, here's what I need to do with the 1999 project Suburban;
1. Leave the 1996 HB in the 1999 as it is now.
2. Remove the 1996 MC and antilock brake module from Suburban and set 'em on the floor
3. Re-install the MC and antilock brake module that originally came from the factory with 1999 Suburban.

The MC should then match the smaller 6-bolt wheels and brakes, and the 1999 module will more likely work with the '99 pcm.

How'd I do this time?

 

[Burning oil]

I would say put 99 stuff back on except use the HB from 96.

 

[NoDak]

Right on! I'll report in after we make the swap. Thanks man!!!

 

[NoDak]

Well, two strikes.

The '99 master cylinder (from vacuum booster set-up) has a much larger mounting feature. It will not fit in hydro-boost. See picture (about 1-1/2" vs. 2").



The '99 abs control module (that was originally a part of the project suburban) appears to be toast. If it is plugged in, you can't even read the tech two as it must be crossing up the diagnostic line. I had suspected the app, as I was getting intermittent "service throttle" light and forcing idle engine speed.

So now I have to figure out how to source another abs module and which one?

Still gotta sort out the brake booster and or hydro-boost. Do the 1/2 vs. 3/4 rigs have different guts inside the master cylinder? Do they have different settings in the hydro-boost? I have brakes working on all 4 corners, just take alot of pedal pressure.

 

[Burning oil]

Its been to long and I did not reread the whole thred to remember what your doing.
You do have the short rod set up BTW.
Why do you need a new MC? I believe 92-2000 MC with same GVW should work.
With that said, you want a MC the same size as the smaller one so it fits the HB right? Ask auto parts for a 99 3/4 - 1ton MC and see what it looks like.
The size of the piston in MC will have an effect on applied pressure needed.

 

[NoDak]

Yeah, that's what I was thinking. But I believe the parts books are confused with this 1500 suburban with big wheels problem. The original mc would have been correct gvw (small wheel 1/2 ton) but is no good due to being to big at mounting face. The donor truck mc is wrong as it was from a 3/4 ton (big wheel). So, if I go looking for parts for a pickup, I should be good. This project suburban should look like my '95 pickup (small wheels, smaller brakes, semi-floater rearend). As for the long or short rod... the long rod from the vacuum booster is too long to assemble the hydro-boost setup.

 

[Big T]

Why did you opt for the conversion instead of just buying a used diesel Suburban? If you're patient, you can find the Suburbans very cheap.

 

[vegtech]

Oh boy,,,, I just started a conversion my self well more of a body swap. 97 2500 6.5 sub the body was junk. Got a low miles 99 1500 5.7 sub at the auction for $625 in the no run section. Fixed a fuel line and been driving it for a month while I stripped the body off the 97. It now sitting naked with the bumper and core support lifted with the 3 inch body lift. I start the final stage of lifting off the 99 body and putting it on the 2500 frame Friday morning and it needs to be driven on Monday morning. Good times a coming.

 

[NoDak]

Why did you opt for the conversion instead of just buying a used diesel Suburban? If you're patient, you can find the Suburbans very cheap.

Perhaps the reason is simply that I need to have my head examined by a professional? LOL

Actually started out needing a ride with more seats, but got distracted by a fuel economy experiment. With the exception of having 4wd (instead of 2wd), and a stiffer APP spring, we have most every mileage making part on board.

Just recently got to driveable status with improvements needed.

Project started in August of 2007 with the purchase of a wrecked donor pickup. The first fuel fill was in October of 2010 (45 gallons from dry). Second fuel fill was in November of 2012 (38.8 gallons, 305 miles, 7.9 mpg, in/out of shop, short test drives). Third fuel fill was this month (19.1 gallons, 243 miles, 12.8 mpg, in/out of shop, in-town driving and out of town test runs).

At this point, pretty well committed to finishing the project.

 

[NoDak]

Oh boy,,,, I just started a conversion my self well more of a body swap. 97 2500 6.5 sub the body was junk. Got a low miles 99 1500 5.7 sub at the auction for $625 in the no run section. Fixed a fuel line and been driving it for a month while I stripped the body off the 97. It now sitting naked with the bumper and core support lifted with the 3 inch body lift. I start the final stage of lifting off the 99 body and putting it on the 2500 frame Friday morning and it needs to be driven on Monday morning. Good times a coming.

How did this little weekend project go down????

 

[NoDak]

Update...

Got a new brake master cylinder to assure I have the right part. There is a much better "feel" in the pedal, but not the only problem if it was a problem.

I believe the hydro-booster is not functioning properly. It still takes way too much pedal force to stop. I have also determined all four wheels are braking. I can let off the throttle and coast, then dive on the brakes really hard and still turn the steering wheel. So it doesn't really look like a power steering pump issue. Brake have priority over the steering. The parts books indicate the hydro-booster should be same between the '96 and '99 for 1/2 and 3/4 ton. So, I'll throw a new hydro-booster at it anyway. The donor booster sat on the donor truck for years. Who knows, it could have failed before I bought it. But since the rig wasn't really road worthy, I didn't or couldn't really test it before taking the diesel donor apart.

The '96 vintage anti-lock brake control module is the wrong p/n for this rig, so I set that aside. The '99 vintage anti-lock brake control module should have been correct for either gas or diesel, but it wigged out everything including the tech2. It must have been either grounding the diagnostic connection, or shorting it to 12 volt? Also blew the fuse. Funny thing is, it worked fine before chopping up the project gaser? I sent it to myairbags.com and they said it was not repairable, thus scheit-canned. So, I got one from used auto parts and we are good to go. Of course, a new fuse too.

We still read this code on the tech2, no service engine soon light thouh; U1000 loss of communitcation with class 2 serial date. Could this be due to using an pcm for an auto-4wd vehicle and we've converted it to a push-button-4wd? That auto-4wd module isn't there? This comes back immediately after resetting codes.

Another peculiar thing... We reset codes and all seems good. Cruise control works. Then after awhile I turn on the Gear Vendor and activate the auto-shift mode. This mode goes to OD at about 45 mph, then when you get down to 25 mph it shifts back into direct. After an auto shift or two it locks me out of cruise control. I suspect a manual shift of the OD would do the same? If I recall correctly, it sees some issue with the vehicle speed input? Ever hear that complaint with a Gear Vendor OD? That fault has to see 1/2 the calculated vehicle speed or greater than a 20 mph difference. Hmm? GV is only a .78 OD. But maybe there is something in the switch from the vssb to the GV-vssb?

Over and out for now!

 

[NoDak]

That should be "serial data" not "serial date".

Also, still have "security" light on. Could that also be related to the missing auto-4wd module? Or the fact that we've mixed and matched all kinds of different parts?