2004 Yukon XL 2500 LBZ

[JayTheCPA]

They left him and I believe went overseas for armour plating and such.

That is interesting seeing the Government has a requirement to source from within the US . . .

Or, perhaps they were armored somewhere else and then sent overseas . . .?

And yes, no more 2500 Burb. They stopped in 2010 iirc, and around 12/13 they started building the government only issue 2500 burbs(most get sold to foreign governments I believe).

Am seeing where the 2500 Burb stopped for the consumer market in 2013. A recent vehicle search for a family member did turn-up a fair amount of 2012 and 2013 models that appeared to have LE rigging in them that was removed. We scored a 2012 with the 6.0 gasser; it too had stuff that was removed and from what we can guess the equipment was some sort of radio system (2 way) and alarm.

GM does look like it is trying to make the new Burb's tow capable again but, for the price point, Ford and Nissan have arguably just as capable platforms for a very competitive price.

 

[BigDogYJ]

We enioy hearing it. And not that anyone wants a bash on anyone thread. He has a good reputation. It is important fpr people to understand that a swap like this is a very complex undertaking, even if the person/ shop has done bucket loads of them already. There is ALWAYS kinks to work out.

Documenting your experience here will help others not just if they use him, but anyone else or doing it themselves.

Take pics of each problem as it arises. Stop and buy a fuel cap, saving receipt and take pic for email to Eric. Then stop at a self service car wash to clean fuel of paint and spray down engine. It is gonna get wet, might as well find issues now from it if any arises and get rid of Armor Hell oops I mean Armor All. Yes I agree, oil to make it shiney is dumb.

Many parts stores have loaner tools, maybe when you get fuel cap you can get torque wrench and socket needed to retorque pitman/ idler/ etc?

Yeah I’m feeling a lot better about this, especially after sleeping on it. I fully agree this stuff is pretty minor in the the grand scheme of things.

Everything I have seen/read/heard about these swaps from Eric is that usually the customer never meets him face to face. They ship everything to them, and Eric ships it back once done. Which leads me to assume that the truck is damn near perfect when it arrives. While this is probably 99% accurate with a new/newer truck/suburban, I have to remind myself this is a 14 year old truck and things aren’t always perfect.

I am glad I came to pick it up. I feel most if not all of these things would have been addressed if he had it for another week.

ALOT of this boils down to my assumed expectations and reality. I fully respect Eric and his work. At this point, I would fully trust him to do another build for me. I am expecting this thread to be used as documentation of my experience and what others can expect with doing this kind of conversion on an older vehicle.

Thanks for the support and following along.

 

[WarWagon]

Thanks for the emmisions info!

Even a new vehicle can have problems. However doing things by hand vs an assembly line can be better or worse. Neither is perfect, but, one has an opportunity to double-check hand work. Or look around and see if anyone noticed one's screw up...

At one time I preferred to drive our 1993, Patch over a 2007 Lemon Trailblazer SS. So new has nothing to do with enjoyable or reliable.

 

[BigDogYJ]

Made it another 400 miles today.
No issues.

Averaging ~20mpg @75mph.
Staying in Raonoke Rapids,NC this evening.

 

[THEFERMANATOR]

Ok, a few things. The relay wiring is out of his control. Due to how GM integrated everything into a molded fuse panel, that's about the only way to do it. GM triggers that relay via the ignition switch for gassers, but diesels trigger it via the ECM. If you don't have that jumpered relay, it will still run, but gives you a p1621 iirc. With that molded panel, there is no eady way to just cut a couple of wires to install it, so he uses that setup. As to your fuel guage, he uses all stock GM programming, so he uses a stock cab and chassis file for the ecm tuning to make 1 fuel guage show the fuel for both tanks, and to run the transfer pump that moves fuel from the rear tank to the front tank. In a cab and chassis truck both tanks are close to the same size, but the total volume is similiar. In a burb, 1 tank is only about half the size of the other tank, so this creates some issues with the guage, but it still works. I posted up a dual tank duraburb tune file here in our library, but it may require some tweaking to the tank voltages as each swap seems to be unique. The only way to make the guage perfect is a custom tune, and Eric strives to use all stock GM components whenever possible, so that is your guage issue. I don't see how anything he did could have made the steering tight. The cognitos aren't on anything that rotates, they lock down to stationary points. I would suspect the pressure valve in your pump as that is a known issue with the duramax pump. As to the abs, yes you need a tech 2 to actuate the pump and bleed it out. This normally isn't required unlesd somebody turned the key on before the brakes were bleed. Once that happens, you're screwed and better break out the pressure bleeder, tech 2, a helper, and earplugs for the cussing. It's time consuming to say the least to bleed out an abs unit once it gets air in it.

I can help you with the tune to get the guage right, or even send you a stock trans safe dsp5 tune for it if you're interested. And if you could, scan the tune in it out for me. My duraburb tune file uses a kodiak tank segment, I've wanted to get a 3500 cab and chassis one for awhile now to compare it to.

 

[FellowTraveler]

Nice project......just one question; what capacity is shown on the placard of that 2500 suspension on the Burb?

 

[BigDogYJ]

Ok, a few things. The relay wiring is out of his control. Due to how GM integrated everything into a molded fuse panel, that's about the only way to do it. GM triggers that relay via the ignition switch for gassers, but diesels trigger it via the ECM. If you don't have that jumpered relay, it will still run, but gives you a p1621 iirc. With that molded panel, there is no eady way to just cut a couple of wires to install it, so he uses that setup. As to your fuel guage, he uses all stock GM programming, so he uses a stock cab and chassis file for the ecm tuning to make 1 fuel guage show the fuel for both tanks, and to run the transfer pump that moves fuel from the rear tank to the front tank. In a cab and chassis truck both tanks are close to the same size, but the total volume is similiar. In a burb, 1 tank is only about half the size of the other tank, so this creates some issues with the guage, but it still works. I posted up a dual tank duraburb tune file here in our library, but it may require some tweaking to the tank voltages as each swap seems to be unique. The only way to make the guage perfect is a custom tune, and Eric strives to use all stock GM components whenever possible, so that is your guage issue. I don't see how anything he did could have made the steering tight. The cognitos aren't on anything that rotates, they lock down to stationary points. I would suspect the pressure valve in your pump as that is a known issue with the duramax pump. As to the abs, yes you need a tech 2 to actuate the pump and bleed it out. This normally isn't required unlesd somebody turned the key on before the brakes were bleed. Once that happens, you're screwed and better break out the pressure bleeder, tech 2, a helper, and earplugs for the cussing. It's time consuming to say the least to bleed out an abs unit once it gets air in it.

I can help you with the tune to get the guage right, or even send you a stock trans safe dsp5 tune for it if you're interested. And if you could, scan the tune in it out for me. My duraburb tune file uses a kodiak tank segment, I've wanted to get a 3500 cab and chassis one for awhile now to compare it to.

Thanks for the info Ferm! I knew you’d have some points to share.
Yeah I looked a little more into the relay wiring thing. I agree it seems that’s the simplest way to make it work without hacking the thing up. Also, while I had him take care of a few last minute things, he let us drive another rig (08 LMM?) that was already converted and the relay wiring was done the same way. I was just a little nervous seeing it there originally without any terminals, just the wire ends shoved into the slots. Seems good now with the right terminals on there.

So far the fuel gauge has been pretty consistent (shows full when its full, drops 1/8th within 50 miles, then it hangs till about 250 miles in then it starts the drop pretty quick, but steady to about half as I continue to drive till about 350 miles. At that point, I fill up and it takes about 17 gals. This has happened 3 times so far and almost dead on each time. So at least its consistent. I haven’t had the guts to go any further yet, but I might once I get closer to home.

For the steering, I agree with you re the cognito braces. It just seems weird as it wasn’t there before. But there’s definitely some resistance / definitive dead spot in the center (about 3” of travel before it engages either direction). I’m gonna pull the braces off at our next stop (but that wont be till Colorado) to see if it changes anything. Otherwise I’ll have to tear into it when I get back home.

I assume they had to crack open the brake lines near the ABS/EBCM since he mentioned they use the EBCM from the pickup/donor. But he said they just do a vacuum bleed. It’s definitely spongy and in a parking lot the brakes feel like they are inconsistently grabbing (just the front). It’s hard to explain. I almost want to say it acts like the front rotors were coated in oil. It stops if you really get on the pedal, but it just feels spongy and needs more effort than before. The pedal was definitely solid before. According to Eric, the only components changed were the EBCM and the rear calipers when they changed the rear axle to the 11.5. I’ll check it out more when I get home. I don’t have a Tech2, but a buddy has a snap on Solus edge. I think it can run the ABS bleed procedure. I’ll have to give that a shot back home.

Yeah I’ll get my v2 hooked up when I get back and show you what I have in there now. Btw, I was running your tow tune (pulled from that DSP5) in my Dually (same motor) for the past 4 years. I was too lazy to hookup the DSP5 switch so I just broke it down into 5 individual tune files and loaded it separately. I’ll probably put a switch in now. the tow tune ran great. I added the turbo brake feature to it and just ran it like that all the time. I had a turbo overboost code a few times when towing/hauling up/down steep grades, but otherwise it was solid. The overboost codes were most likely me not getting the commanded vs expected boost when off the throttle.

Thanks again for all the advice/info.

BTW, rolled into Niagara Falls tonight. We’ve got almost 1500 miles on it since the swap. We’ve avg’d 20MPG the whole way up. I’m very happy with this right now. More updates to come.

 

[Ed HD]

I can help you with the tune to get the guage right, or even send you a stock trans safe dsp5 tune for it if you're interested. And if you could, scan the tune in it out for me. My duraburb tune file uses a kodiak tank segment, I've wanted to get a 3500 cab and chassis one for awhile now to compare it to.

Random/off topic: the GMC 4500 my dad's company has has 2 filler necks, but I never have to switch tanks. I always wondered about that. The front usually takes about 25 gallons, and the rear 10-15. It just pumps fuel from the rear tank into the front until the rear is empty? You can PM me if you like, to keep this more or less on-topic.

Glad the swap went well and things are running for you BigDog!! Hopefully you can work the kinks out in short order. Like you said, putting parts from a couple 15 year old trucks together can have its difficulties.

 

[THEFERMANATOR]

Random/off topic: the GMC 4500 my dad's company has has 2 filler necks, but I never have to switch tanks. I always wondered about that. The front usually takes about 25 gallons, and the rear 10-15. It just pumps fuel from the rear tank into the front until the rear is empty? You can PM me if you like, to keep this more or less on-topic.

Glad the swap went well and things are running for you BigDog!! Hopefully you can work the kinks out in short order. Like you said, putting parts from a couple 15 year old trucks together can have its difficulties.

Starting with the gmt-400 trucks, GM set them up so the engine runs on 1 tank only, and it transfers fuel from the 2nd tank over to it. They used a balance module on early trucks to handle the fuel transfer and convert 2 tank signals to 1 output for a single guage. Once they got controllers with enough processing power, they did away with the balnce module, and moved it all to the ecm/pcm. It logs the fuel quantity in each tank to know how much fuel is in each, then gives a guage output of the 2 tank volumes vs total tank volume for the guage. Once the main tank gets down to roughly 3/4, it will start activating the transfer pump to move fuel to the main tank to try and keep the front tank around 1/2-3/4(thanks to testdrive for logging this algorythim in detail for me) until the rear tank is empty. All pickups used 2 tanks and 2 fillers for the tanks, but 2500 subs had 2 tanks and 1 filler with a y hose for the filler to fill both tanks.

Also of note, if the ecm detects any problems with the system like it not detecting fuel transferring, a sender staying in 1 spit too long, or the fuel level going up on it's own(like refueling), it will default the guage to empty. GM did change some later calibrations to account for refueling with the engine running, but it doesn't always work, and you may have to turn the key off and back on to make the guage work again.

 

[THEFERMANATOR]

Thanks for the info Ferm! I knew you’d have some points to share.
Yeah I looked a little more into the relay wiring thing. I agree it seems that’s the simplest way to make it work without hacking the thing up. Also, while I had him take care of a few last minute things, he let us drive another rig (08 LMM?) that was already converted and the relay wiring was done the same way. I was just a little nervous seeing it there originally without any terminals, just the wire ends shoved into the slots. Seems good now with the right terminals on there.

So far the fuel gauge has been pretty consistent (shows full when its full, drops 1/8th within 50 miles, then it hangs till about 250 miles in then it starts the drop pretty quick, but steady to about half as I continue to drive till about 350 miles. At that point, I fill up and it takes about 17 gals. This has happened 3 times so far and almost dead on each time. So at least its consistent. I haven’t had the guts to go any further yet, but I might once I get closer to home.

For the steering, I agree with you re the cognito braces. It just seems weird as it wasn’t there before. But there’s definitely some resistance / definitive dead spot in the center (about 3” of travel before it engages either direction). I’m gonna pull the braces off at our next stop (but that wont be till Colorado) to see if it changes anything. Otherwise I’ll have to tear into it when I get back home.

I assume they had to crack open the brake lines near the ABS/EBCM since he mentioned they use the EBCM from the pickup/donor. But he said they just do a vacuum bleed. It’s definitely spongy and in a parking lot the brakes feel like they are inconsistently grabbing (just the front). It’s hard to explain. I almost want to say it acts like the front rotors were coated in oil. It stops if you really get on the pedal, but it just feels spongy and needs more effort than before. The pedal was definitely solid before. According to Eric, the only components changed were the EBCM and the rear calipers when they changed the rear axle to the 11.5. I’ll check it out more when I get home. I don’t have a Tech2, but a buddy has a snap on Solus edge. I think it can run the ABS bleed procedure. I’ll have to give that a shot back home.

Yeah I’ll get my v2 hooked up when I get back and show you what I have in there now. Btw, I was running your tow tune (pulled from that DSP5) in my Dually (same motor) for the past 4 years. I was too lazy to hookup the DSP5 switch so I just broke it down into 5 individual tune files and loaded it separately. I’ll probably put a switch in now. the tow tune ran great. I added the turbo brake feature to it and just ran it like that all the time. I had a turbo overboost code a few times when towing/hauling up/down steep grades, but otherwise it was solid. The overboost codes were most likely me not getting the commanded vs expected boost when off the throttle.

Thanks again for all the advice/info.

BTW, rolled into Niagara Falls tonight. We’ve got almost 1500 miles on it since the swap. We’ve avg’d 20MPG the whole way up. I’m very happy with this right now. More updates to come.

Sounds like you're barely usi,g half your available fuel. I believe total available fuel is 32 or 36 gallons for the dual tank burbs.

 

[Ed HD]

Starting with the gmt-400 trucks, GM set them up so the engine runs on 1 tank only, and it transfers fuel from the 2nd tank over to it. They used a balance module on early trucks to handle the fuel transfer and convert 2 tank signals to 1 output for a single guage. Once they got controllers with enough processing power, they did away with the balnce module, and moved it all to the ecm/pcm. It logs the fuel quantity in each tank to know how much fuel is in each, then gives a guage output of the 2 tank volumes vs total tank volume for the guage. Once the main tank gets down to roughly 3/4, it will start activating the transfer pump to move fuel to the main tank to try and keep the front tank around 1/2-3/4(thanks to testdrive for logging this algorythim in detail for me) until the rear tank is empty. All pickups used 2 tanks and 2 fillers for the tanks, but 2500 subs had 2 tanks and 1 filler with a y hose for the filler to fill both tanks.

Also of note, if the ecm detects any problems with the system like it not detecting fuel transferring, a sender staying in 1 spit too long, or the fuel level going up on it's own(like refueling), it will default the guage to empty. GM did change some later calibrations to account for refueling with the engine running, but it doesn't always work, and you may have to turn the key off and back on to make the guage work again.

Good info! I always wondered how that worked.

 

[BigDogYJ]

Sounds like you're barely usi,g half your available fuel. I believe total available fuel is 32 or 36 gallons for the dual tank burbs.

Yeah so the past few fillups I have gotten a little more comfortable and ran 536 miles between fillups. Fuel gauge showed 1/4 tank left. It took 28.15gal to fill back up. That’s a solid 19mpg. Averaging 80-85mph from Evergreen CO to Beaver, UT. I can’t complain with that. Especially considering all the passes we climbed over along the way. Still running great. One more stop tonight then we should be back home tomorrow. So far 4200 miles since the conversion.

 

[BIGR]

Yeah so the past few fillups I have gotten a little more comfortable and ran 536 miles between fillups. Fuel gauge showed 1/4 tank left. It took 28.15gal to fill back up. That’s a solid 19mpg. Averaging 80-85mph from Evergreen CO to Beaver, UT. I can’t complain with that. Especially considering all the passes we climbed over along the way. Still running great. One more stop tonight then we should be back home tomorrow. So far 4200 miles since the conversion.

Glad things are working out for you, definitely putting it through the test.
Sounds like you kept any soot blowed out of it as they say and that's pretty good dang fuel mileage. I know how it is, out west in those wide open spaces with good roads. Went out there in 2006 (Truck had 3400 miles on it)and would cruise on those big nice roads, eat those mountains up like nothing and got an average of 17.39 MPG and could get 19.8 MPG driving 70 to 75 MPH. I think the truck hit the rev limiter a few times to get out of a few situations I didn't want to be in.

 

[btfarm]

Interested in what speed gives the best mileage. On my LBZ 70-75 is optimum

 

[THEFERMANATOR]

Mine seems to do its best at 65. I did 23 on 1 tank keeping it under 65. Testdrive said his was did it's best right around 65 as well. With my econ tune he said he could almost hit 22 running 70-75.

 

[DieselSlug]

Mine seems to do its best at 65. I did 23 on 1 tank keeping it under 65. Testdrive said his was did it's best right around 65 as well. With my econ tune he said he could almost hit 22 running 70-75.

These numbers are real close to what I get with the little EcoDiesel. Impressive for a monster SUV.

 

[BigDogYJ]

Im really impressed with the range per fillup. We made it home Monday afternoon. I’ve been commuting the rest of the week 30-35 mins in traffic each way and will probably fill up tomorrow.
I did get a chance to get my Westin bars installed tonight. I’ll get pics tomorrow.
Also solved my steering woes... the bolt that holds the intermediate steering shaft to the “primary shaft from the gear box?” was only threaded in 2-3 threads. Hmmm. Tightened that up and now it’s like it used to be. Still gotta go through this thing with a fine tooth comb. Tightening that up solved the dead spot in the steering wheel. Should have looked at that before the 5k mike trip... oh well.
Next I gotta run the abs bleed procedure and make sure no more air in the lines. The brakes still feel a little funny. Little by little getting everything resolved. Another 800 mile trip coming up in a few weeks, so I’d like to get the brakes figured out by then. Still really enjoying this rig.

 

[BigDogYJ]

18mpg on the latest fill up with half of it being in town driving. Not bad.
Tightening up the intermediate steering shaft bolt made a huge difference in the feel of the front end. No more weird creaking or rattle in the steering wheel. Really happy that was all it was.



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[btfarm]

That loose connection could easily have been disastrous in your cross country run...

 

[BigDogYJ]

That loose connection could easily have been disastrous in your cross country run...

Yeah it got a little hairy in cross windows and passing semi’s. I really should have worked on that earlier. Thank God he kept us safe.


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