Topic: 2002 Suburban 2500 build thread, Part 4

[Flyin6]

John is refurbishing a used valve body with the spected springs, valves, and other unique Sonnax parts

[Flyin6]

John noticed something that may have accounted for the O2 sensors, heaters not working properly. He found an ECM harness ground not attached. Who knows, could this be the cure?

[Flyin6]

The burb's other room mates

That Camaro has some strange rubber

He used it for some mud drags at the fair a week or two ago...strange!

[Flyin6]

Sonnax parts and outgoing Trans-go junk

[Flyin6]

I'm hoping all that stuff isn't hanging around much longer!

[Flyin6]

A look around John's shop

S&S Transmission and car care
Alexandria, KY

[JR]

I like the coffee table...

[Bigdave_185]

Really a clean looking burb.  Hope this is the fix


Sent from my iPhone using Tapatalk

[Flyin6]

Really a clean looking burb.  Hope this is the fix


Sent from my iPhone using Tapatalk

It is like that everywhere. Every time I pulled off a panel, I found only dust. No rot, no accumulation of dirt, no signs of mice, no rust or corrosion. It all seemed almost like new except for the rear axle area that had some dirt scattered about, no doubt from use. I have taken it off road in gooey mud, but it cleaned up nice thanks to blue beacon truck wash!

[Flyin6]

OK, I have the Suburban back

The CEL is off now and the engine is making a bunch of power. Not diesel power, but a whole lot more than before.

The converter was sold to me as a 2600 stall converter. It is not. John was exactly correct in saying all along that you can't get a low stall in a smaller diameter TC. We stalled it against the brakes and it finally spun the rear tires in gravel at 3300 RPM. If I drive light throttle in traffic it will tach around 2600 until it either gets to speed or the converter locks up.

Speaking of the lockup, it is like being bumped in the rear by a car moving 5mph. It hits pretty hard, and I confess I have never seen that before. I also believe I may be able to sort that out with tuning.

The shifting is now butter smooth. That's great. Overall I'd say I am 70% of the way there. It stalled once when cold, something it should never do, so that has to be looked into. John thinks the thing is pretty powerful and hauls the mail. I guess I am just used to my D-Max truck because it does not feel fast to me, well, maybe sometimes.

So today I went into the test/tune mode.

First I cleared the DTC's. And I have no new ones, so perhaps the O2 sensor heater thing is fixed with the reattachment of that dangling ground wire.

I went into the transmission tune and changed everything in there to a tune I found on line for a 6.0, 2002 Silverado non-HD. Comparing the trans files, I liked those better. I tried to correct the fuel gage which now only reads 3/4 when full, but so far no-Bueno on that count. I also readjusted tire size to what John suggested, that is programming in the exact tire height. I can tell you that is wrong after doing it. I was indicating 80 on the highway and all the traffic was passing me, so I went back in and subtracted .5" from the listed 36.7" height Kanati states for the tire height.

I pumped the tires up to 40 and put 60 lbs in the air bags. The ride was sloppy, but tightened up, so that was a net-positive.

On the tuning side, I have a gentlemen, one of the very best interested in tuning the truck. I have to work through John as he does not like the public to know of his work, but he is the guy who broke the GM unbreakable code. He wrote the blue cat transmission tuning program and he is who HP tuners calls in to fix their messes. He will add the final touches to the truck and make it all that it can be.

At the moment it is very capable of just about anything. I think it could drive across country towing my camper. It should only improve from here.

[JR]

Glad you are getting there. TO bad it took this long a couple "tuners" to find issues.

Try playing with the tank size. Mine still reads full OK, but starts to move slow then dumps. When the light comes on (rarely when going to NV to fill) I still 10 gal in there.

Same with tire size, finally got it 1mph under, which I can live with.

[Flyin6]

Glad you are getting there. TO bad it took this long a couple "tuners" to find issues.

Try playing with the tank size. Mine still reads full OK, but starts to move slow then dumps. When the light comes on (rarely when going to NV to fill) I still 10 gal in there.

Same with tire size, finally got it 1mph under, which I can live with.

Copy that JR, still tweaking
But with my fuel issue, all at once the gage no longer reads full after I fill up. Now it will only go to 3/4 full on the gage. That happened right after reloading a major tune change which has me thinking I turned something off without knowing it.
But
With that problematic 6 gallon factory aux tank sitting in there, it makes me wonder if that simply stopped working properly.
If I understand it properly, when you are filling the tank, you are actually filling the 6 gal aux tank and that is spilling over into the 31.5 gallon main tank. Then later on a second electric pump located in the aux tank pumps the remaining fuel over into the high pressure side of the supply line to feed the engine until it is exhausted, then some low fuel level sending unit in the aux tank cuts power to that pump and the main tank pump takes over.
That could point to a malfunction of that aux pump setup...Dunno...

[rpar86]

Have you ruled out the stepper motor in the gauge cluster being bad? They’re known to do that.

[Flyin6]

Have you ruled out the stepper motor in the gauge cluster being bad? They’re known to do that.

Have not?
Hmmm another element to consider
So you're saying this stepper motor failure will manifest in this very manner? I ask because I have never heard nor seen anything like that before

[JR]

There are many places that rebuild and upgrade all the lights to LED.

[rpar86]

The stepper motors just start acting “weird”. Not reading right when they always have before, going past their min/max, etc.

 The fact that it started happening right after you changed the tune is suspicious though.

Like JR says, plenty of places that rebuild those clusters all the time.

Now after saying this, yours is an 02 and might not be applicable given what I’m seeing here.

https://www.gmgaugerepair.com/chevrolet-instrument-cluster-repair/digital-gauge-cluster/

[Flyin6]

The stepper motors just start acting “weird”. Not reading right when they always have before, going past their min/max, etc.

 The fact that it started happening right after you changed the tune is suspicious though.

Like JR says, plenty of places that rebuild those clusters all the time.

Now after saying this, yours is an 02 and might not be applicable given what I’m seeing here.

https://www.gmgaugerepair.com/chevrolet-instrument-cluster-repair/digital-gauge-cluster/

Looks like 2003 up, not 2002.
I wonder what changed?

[TexasRedNeck]

The can bus communication protocol changed, which is why on later models you can drop in a later model engine and do a re-learn.  2001-2002 are the least compatible.


Sent from my iPad using Tapatalk

[Flyin6]

The can bus communication protocol changed, which is why on later models you can drop in a later model engine and do a re-learn.  2001-2002 are the least compatible.


Sent from my iPad using Tapatalk

"Why me!!!!!!!"

[TexasRedNeck]

The can bus communication protocol changed, which is why on later models you can drop in a later model engine and do a re-learn.  2001-2002 are the least compatible.


Sent from my iPad using Tapatalk

"Why me!!!!!!!"

Well we are in the same boat


Sent from my iPhone using Tapatalk

[KensAuto]

The can bus communication protocol changed, which is why on later models you can drop in a later model engine and do a re-learn.  2001-2002 are the least compatible.


Sent from my iPad using Tapatalk

"Why me!!!!!!!"

Because you're the one that hacked up a clean one owner?
Still love you boss.

[JR]

 

[oklawall]

The can bus communication protocol changed, which is why on later models you can drop in a later model engine and do a re-learn.  2001-2002 are the least compatible.


Sent from my iPad using Tapatalk

"Why me!!!!!!!"

Because you're the one that hacked up a clean one owner?
Still love you boss.

Do I see a firing in your future?

[KensAuto]

The can bus communication protocol changed, which is why on later models you can drop in a later model engine and do a re-learn.  2001-2002 are the least compatible.


Sent from my iPad using Tapatalk

"Why me!!!!!!!"

Because you're the one that hacked up a clean one owner?
Still love you boss.

Do I see a firing in your future?

Reverse psychology, I'm shooting for another raise.

[JR]

Lets just let H deal with this,,,,,,,,,,,

[TexasRedNeck]

H would slander Don with a full court media press aided by her cronies.  Say that he beat baby seals for fun in Afghanistan. If that didn’t work, Don would die from some mysterious cause.


Sent from my iPhone using Tapatalk

[Flyin6]

The can bus communication protocol changed, which is why on later models you can drop in a later model engine and do a re-learn.  2001-2002 are the least compatible.


Sent from my iPad using Tapatalk

"Why me!!!!!!!"

Because you're the one that hacked up a clean one owner?
Still love you boss.

Do I see a firing in your future?

I thought about if for a minute, then realized it's thanks-givin'.
So although I wasn't givin any thanks for the hackin' komment, I guess I was givin' a bit
I'm givin' the sun burnt trouble maker a little grace! ;-)

[Flyin6]

The can bus communication protocol changed, which is why on later models you can drop in a later model engine and do a re-learn.  2001-2002 are the least compatible.


Sent from my iPad using Tapatalk

"Why me!!!!!!!"

Because you're the one that hacked up a clean one owner?
Still love you boss.

Do I see a firing in your future?

Reverse psychology, I'm shooting for another raise.

It didn't work!
Git back to work!

[Flyin6]

H would slander Don with a full court media press aided by her cronies.  Say that he beat baby seals for fun in Afghanistan. If that didn’t work, Don would die from some mysterious cause.


Sent from my iPhone using Tapatalk

Those things were seals?

[Flyin6]

So after a bunch of tinkering with the tune (Trans only) I think this thing is a fail.

Ya, no getting around it. The new converter revs the engine all the time and will unlock the moment you get out of it (Tuning issue)

When the converter locks you get good power from the engine. With that supercharger you can push up any hill at 70 with just boost.

But the engine is always working. I think I have the speedo dialed in which gave me my first good fuel mileage check.

Gents, its awful, much worse that I ever imagined. So no towing and light cruise it just delivered 7.63 mpg over a 225 mile loop.

There is no amount of tuning that will ever fix that. The converter is a fail and absolutely does not do what Circle-D said it would do. It's not even close. They sold me a bill of goods. I asked for a low stall and I got a triple disc unit that will lock somewhere from 2800-3300 RPM.

I do have the best tuner in the country interested in it, but that is more $$$ and I am done with this. It will never be a useful truck. Sure I can toss a grand here and another there and get it to one out of three things but to ever be able to tow and get mileage, well that is no where near any reality I could achieve.

So my plan from here is:
1. Not to spend any more money on it
2. Not to go forward with more tuning unless its free
3. Either sell the thing outright
4. Or, if that doesn't happen then the motor comes out

Should I decide to go with option 4, then I will procure a non electronic 6BT, rebuild it to near stock and install it with the stock 4L80E and drive that.

As a lesson learned. Gas engines just can't move weight around efficiently. Yea they can get a camaro down the strip in 10 seconds but in a big truck with big tires they are useless, and frankly, I hate them. I would have said they are junk but I think the performance speaks for itself

I guess my Suburban project with the gas engine is one huge, strike that, one titanic failure!

[JR]

Square D all over,,,,,,,,ouch.

Since everyone who knows anything is saying the TC is junk, send it back. Sure you can challenge the charge if they fight it.
 
If not I can understand the 6BT, but why a 4L80? I keep thinking about keeping my 46R, but going with a tap shift.

[oklawall]

Sad news I had hopes that you could make this work

[Flyin6]

Square D all over,,,,,,,,ouch.

Since everyone who knows anything is saying the TC is junk, send it back. Sure you can challenge the charge if they fight it.
 
If not I can understand the 6BT, but why a 4L80? I keep thinking about keeping my 46R, but going with a tap shift.

I'm going to send it back and demand my money back. Of course I will lose the $1,000 R&R charge

[wyorunner]

Square D all over,,,,,,,,ouch.

Since everyone who knows anything is saying the TC is junk, send it back. Sure you can challenge the charge if they fight it.
 
If not I can understand the 6BT, but why a 4L80? I keep thinking about keeping my 46R, but going with a tap shift.

Sure I’ve only got 5000 miles on our 46rh, less than 1000 after rebuild, but I often wish I’d have put something different. But, it was cheapest, was present, and required no modification so we ran it.

The one huge down side of the 46rh is parts are becoming more and more limited by the day. Torque converters are ridiculous, core charge is 900 most places.

All that to say, something like a 4l80 makes some sense to me.

[TexasRedNeck]

Don I believe the Allison will fit behind it and be compatible with your controller system although only the five speed on your 2001 unless you do the 5-6 speed valve body upgrade. The 8.1 came with it.

That would solve your trans/tc problems.

Fuel mileage is still going to be a concern but should get better with less slippage. Doubt you’ll get over 10


Sent from my iPhone using Tapatalk

[Flyin6]

Don I believe the Allison will fit behind it and be compatible with your controller system although only the five speed on your 2001 unless you do the 5-6 speed valve body upgrade. The 8.1 came with it.

That would solve your trans/tc problems.

Fuel mileage is still going to be a concern but should get better with less slippage. Doubt you’ll get over 10


Sent from my iPhone using Tapatalk

Tex, when you look at just solving an issue like a transmission/torque converter problem but then still only having a 10 mpg (unladen) max, that's just plain stupid.
This combo is untenable, and I should have realized it earlier.
If all I wanted was a Saturday night cruiser with a lot of stoplight to stoplight git-up-n-go, then it may have a role, but I wanted it as a trans-America vehicle hauling my camper.
I'm going to have to turn the page in this book and start a new chapter I feel.

As a final last resort, I just tossed it a life preserver in the form of an email to this genius tuner John speaks of. I'll bet that he concurs with me with the 6BT transplant idea.

[dave945]

Just to be the weird one in the group, I really don’t understand why you aren’t able to get better mileage out of it. I’m running the same engine(minus tuning, cam, supercharger and big tires). I regularly get between 12-14 mpg, and that is combination back roads and highway, with me sometimes making the kids happy when they say “go faster daddy”.  Not to mention this is a 3/4 ton van with 500k miles on it. Something just doesn’t sound right to me. Maybe your transfer case is stuck in 4wd, maybe you’re just pouring gas on the ground when you are driving it around, but to me it seems illogical.

Just my two cents from a Dave that served in the Air Force.  Let the gaming begin. ;)


Sent from my iPhone using Tapatalk

[JR]

I think in the long run a diesel is the way to go with what you want. I agree, you built a sat night cruiser engine.

Can a TC cost you 50% in your mileage, you bet.

I like the allison idea over all, came in lots of things.

[EL TATE]

Just to be the weird one in the group, I really don’t understand why you aren’t able to get better mileage out of it. I’m running the same engine(minus tuning, cam, supercharger and big tires). I regularly get between 12-14 mpg, and that is combination back roads and highway, with me sometimes making the kids happy when they say “go faster daddy”.  Not to mention this is a 3/4 ton van with 500k miles on it. Something just doesn’t sound right to me. Maybe your transfer case is stuck in 4wd, maybe you’re just pouring gas on the ground when you are driving it around, but to me it seems illogical.

Just my two cents from a Dave that served in the Air Force.  Let the gaming begin. ;)


Sent from my iPhone using Tapatalk

before all the transfercase/torque converter issues popped up, he geared back up to 4.56 from 4.88 when he took out that monster custom military dana 80 thing. now that all the other drivetrain gremlins have been "sorted out" it probably needs the 4.88 back in there so he's not flooring it to get out of his own way. you're averaging 12-14, and he's getting 7+, not really that far off when you think about what it would be like if you added 2000lbs of gear and floored it every time you left a stop.

pay no attention to this man behind the curtain, however. gearing will NOT get you the power you desire Don. Proceed with the diesel swap. fire for effect.

[Flyin6]

Yea, I haven't heard anything from this tuning guy
and
12-13 MPG would not be all that helpful
Thing is, I just don't think that after all this effort, this gasser idea is viable at all, especially when you add in towing.

[JR]

Bingo!!!

[Bigdave_185]

Deja vu anyone?


Sent from my iPhone using Tapatalk

[JR]

Us??? 

[Flyin6]

Deja vu anyone?


Sent from my iPhone using Tapatalk

Well, I'm not going to part this one out, but it is clearly not able to do what I want it to do so something has to change.

I think I have the motor/blower sold for $6K

After the holidays, I think I'll gut the powerplant and try to find a 12 valve. The conversion is not all that complicated I think.
Use duramax radiator and intercooler in stock front clip. Will use 4L80E with a stand alone control harness which is around $475
Give the 12 valve a good rebuild and decent parts going for longevity and reliability over power. Someone makes engine mounts somewhere. Have Circle-D take that incorrectly built converter back and have them build a triple disc low stall for the cummins. Drop it in and spend the next six months figuring out how to re-pin the wiring harness connectors.
Goal is to make it look like it came with that motor and get the electronics/electrics to function normally.
Thinking a 400hp/900Ft/lb build which isn't that far from stock.

[TexasRedNeck]

And 4:11 gears?


Sent from my iPad using Tapatalk

[Flyin6]

And 4:11 gears?


Sent from my iPad using Tapatalk

Sorry, Tex, not trackin' was that a ???

[TexasRedNeck]

Well I would expect a regear with the Cummins back to 411 to take advantage of the torque.


Sent from my iPad using Tapatalk

[JR]

bigger tires might be easier

[Flyin6]

Well I would expect a regear with the Cummins back to 411 to take advantage of the torque.


Sent from my iPad using Tapatalk

No, sorry

No more regearing.

4.10's with the stock 32" tires (or something like that) is very close to 37" tires and a 4.56.
32" tire/ 4.10 (Stock) 2261 @ 70mph
37" tire/4.56             2174 @ 70 mph

If money were not a factor, perhaps I would consider, but at the moment, I am looking at rescuing what amounts to a failed project, so planning around a minimum cash infusion, and betting I will get a lifetime of service out of a very efficient/powerful vehicle.
Lots of earlier generation (92-99) burbs have been swapped with remarkable results. Power, smoothness >20mpg figures and towing all in one package.

[JR]

those are gas numbers, not diesel rpms, but you have od.