6.0 what grade fuel

[Rocket Man]

I have 2 Blackbear Performance tunes available on my Autocal for my LQ4 - for 87 and for 89+. I ran an experiment since I wanted to know if it was worth the extra few dollars every tank to run premium. I ran several tanks on the 89+ tune with premium and there was no increase in power OR mileage. I went back to my 87 tune and regular gas, since if there's no noticeable difference I see no reason to pay more. It's fast with either tune or any octane.

 

[Rocket Man]

I also just noticed I drove 30 min after filling it and used 1/8 of a tank. That's a lot more than normal. When I leave this afternoon I will top off with 93.

That's not an accurate way to test mpg obviously. The only way to test is several full tanks, using a calculator and trip meter, and not the DIC which is only a guess. Also not all station's nozzles shut off at the same level. That station might have tripped the shutoff sooner on the nozzle.

 

[#1taho]

Yeah I agree with both statements. That's why I tuned to 87. But it does seem that at some gas stations the truck burns through it faster.

 

[Kingx1]

How do you know which motor you have? I have a 6.0 in my 94 Yukon 2500 XL

 

[Rocket Man]

How do you know which motor you have? I have a 6.0 in my 94 Yukon 2500 XL

You can look at your RPO codes on the label inside your glovebox. Since yours is a 2500, are you sure you don't have the 8.1l? Here's a partial list:


LQ4 14863 P ENG M ENGINE GAS, 8 CYL, 6.0L, MFI, IRON, GM 960229 E X E A


LQ5 14864 P ENG M ENGINE GAS, 4 CYL, 1.4L, MFI, OHC 940929 E 5 E A

LQ6 14865 P ENG M ENGINE GAS, 6 CYL, 3.2L, SFI, TWIN TURBO, ALUM, 60 DEGREE, GM 20109 E X E A

LQ7 14866 P ENG M ENGINE GAS, 4 CYL, 1.3L, MFI, DOHC, PORT DEACTIVATION 121 E 0 E A

LQ8 14867 P ENG M ENGINE GAS, 4 CYL, 2.0L, MFI, L4, TURBO-LOW, ALUM, DOHC, SAAB 9 2 0 E X E A

LQ9 14868 P ENG M ENGINE GAS, 8 CYL, 6.0L, MFI, IRON, GM, ** 990122 E X E A

LQA 14833 P PWO M POWER OPTION CATERPILLAR 3126, 7.2L, 207 GROSS H.P. @ 2,300 RPM 10312 E T E A

LQB 14834 P PWO M POWER OPTION DURAMAX, 7.8L, 200 GROSS HP @ 2,200 RPM 990112 E T E A

LQC 14835 P PWO M POWER OPTION DURAMAX, 7.8L, 230 GROSS HP @ 2,200 RPM 990112 E T E A

LQD 14836 P PWO M POWER OPTION GMPT V8, 8.1L, 370 NET HP @ 4,400 RPM 825 E X E A

LQE 14837 P PWO M POWER OPTION GMPT V8, 8.1L, 415 NET HP @ 5,000 RPM 825 E X E A

LQF 14838 P PWO M POWER OPTION DURAMAX, 6.6L, 300HP/860LB FT @ 2200 RPM 20610 E T E A

LQH 14840 P PWO M POWER OPTION DURAMAX, 7.8L, 275 GROSS HP @ 2,200 RPM 10904 E T E A

LQK 14843 P PWO M POWER OPTION DURAMAX, 7.2L, 190 GROSS HP @ 2,400 RPM 10312 E T E A

LQL 14844 P PWO M POWER OPTION DURAMAX, 7.2L, 210 GROSS HP @ 2,400 RPM. 10312 E T E A

LQM 14845 P PWO M POWER OPTION GMPT V8, 6.5L, 175 GROSS HP @ 2,800 RPM 980908 E T E A

LQN 14846 P PWO M POWER OPTION GMPT V8, 6.5L, 190 GROSS HP @ 2,800 RPM 980623 E T T A

LQQ 14849 P PWO M POWER OPTION GMPT V8, 8.1L, 210 NET HP @ 3,800 RPM 990112 E X E A

LQR 14850 P PWO M POWER OPTION GMPT V8, 8.1L, 225 NET HP @ 3,600 RPM 10312 E T E A

LQS 14851 P PWO M POWER OPTION DURAMAX, 7.8L, 250 GROSS HP @ 2,200 RPM HIGH TORQ 10904 E T E A

LQV 14854 P PWO M POWER OPTION CATERPILLAR 3126, 7.2L, 250 GROSS H.P. @ 2,200 RPM 980623 E T E A

LQW 14855 P PWO M POWER OPTION CATERPILLAR 3126, 7.2L, 275 GROSS H.P. @ 2,200 RPM 980623 E T E A

LQX 14856 P PWO M POWER OPTION CATERPILLAR 3126, 7.2L, 300 GROSS H.P. @ 2,200 RPM 980623 E T E A

LQY 14857 P PWO M POWER OPTION GMPT V8, 8.1L, 270 NET HP @ 3,800 RPM 981217 E

 

[#1taho]

Great info.


So I did fill up with 93 on my way home. Stopped at BP. The miliage came back up and got the power back. I must have stopped at a ****** gas station and got some bad gas.

 

[Kingx1]

You can look at your RPO codes on the label inside your glovebox. Since yours is a 2500, are you sure you don't have the 8.1l? Here's a partial list:


LQ4 14863 P ENG M ENGINE GAS, 8 CYL, 6.0L, MFI, IRON, GM 960229 E X E A


LQ5 14864 P ENG M ENGINE GAS, 4 CYL, 1.4L, MFI, OHC 940929 E 5 E A

LQ6 14865 P ENG M ENGINE GAS, 6 CYL, 3.2L, SFI, TWIN TURBO, ALUM, 60 DEGREE, GM 20109 E X E A

LQ7 14866 P ENG M ENGINE GAS, 4 CYL, 1.3L, MFI, DOHC, PORT DEACTIVATION 121 E 0 E A

LQ8 14867 P ENG M ENGINE GAS, 4 CYL, 2.0L, MFI, L4, TURBO-LOW, ALUM, DOHC, SAAB 9 2 0 E X E A

LQ9 14868 P ENG M ENGINE GAS, 8 CYL, 6.0L, MFI, IRON, GM, ** 990122 E X E A

LQA 14833 P PWO M POWER OPTION CATERPILLAR 3126, 7.2L, 207 GROSS H.P. @ 2,300 RPM 10312 E T E A

LQB 14834 P PWO M POWER OPTION DURAMAX, 7.8L, 200 GROSS HP @ 2,200 RPM 990112 E T E A

LQC 14835 P PWO M POWER OPTION DURAMAX, 7.8L, 230 GROSS HP @ 2,200 RPM 990112 E T E A

LQD 14836 P PWO M POWER OPTION GMPT V8, 8.1L, 370 NET HP @ 4,400 RPM 825 E X E A

LQE 14837 P PWO M POWER OPTION GMPT V8, 8.1L, 415 NET HP @ 5,000 RPM 825 E X E A

LQF 14838 P PWO M POWER OPTION DURAMAX, 6.6L, 300HP/860LB FT @ 2200 RPM 20610 E T E A

LQH 14840 P PWO M POWER OPTION DURAMAX, 7.8L, 275 GROSS HP @ 2,200 RPM 10904 E T E A

LQK 14843 P PWO M POWER OPTION DURAMAX, 7.2L, 190 GROSS HP @ 2,400 RPM 10312 E T E A

LQL 14844 P PWO M POWER OPTION DURAMAX, 7.2L, 210 GROSS HP @ 2,400 RPM. 10312 E T E A

LQM 14845 P PWO M POWER OPTION GMPT V8, 6.5L, 175 GROSS HP @ 2,800 RPM 980908 E T E A

LQN 14846 P PWO M POWER OPTION GMPT V8, 6.5L, 190 GROSS HP @ 2,800 RPM 980623 E T T A

LQQ 14849 P PWO M POWER OPTION GMPT V8, 8.1L, 210 NET HP @ 3,800 RPM 990112 E X E A

LQR 14850 P PWO M POWER OPTION GMPT V8, 8.1L, 225 NET HP @ 3,600 RPM 10312 E T E A

LQS 14851 P PWO M POWER OPTION DURAMAX, 7.8L, 250 GROSS HP @ 2,200 RPM HIGH TORQ 10904 E T E A

LQV 14854 P PWO M POWER OPTION CATERPILLAR 3126, 7.2L, 250 GROSS H.P. @ 2,200 RPM 980623 E T E A

LQW 14855 P PWO M POWER OPTION CATERPILLAR 3126, 7.2L, 275 GROSS H.P. @ 2,200 RPM 980623 E T E A

LQX 14856 P PWO M POWER OPTION CATERPILLAR 3126, 7.2L, 300 GROSS H.P. @ 2,200 RPM 980623 E T E A

LQY 14857 P PWO M POWER OPTION GMPT V8, 8.1L, 270 NET HP @ 3,800 RPM 981217 E

It's definitely a 6.0...but i dont see anything like that in my glove. You're talking about the "Service Parts Identification" label right?

 

[Tonyrodz]

It's definitely a 6.0...but i dont see anything like that in my glove. You're talking about the "Service Parts Identification" label right?

Look at the sticker on your airbox under the Hood. Hopefully it's still there. It's long and silver/gray.

 

[Kingx1]

I'll have to take a look in the morning cause its dark out and im getting tired.

 

[Rocket Man]

It's definitely a 6.0...but i dont see anything like that in my glove. You're talking about the "Service Parts Identification" label right?

Yes. That list I posted is part of an RPO code list that I use to decipher RPO codes, it's not what you will see in your glovebox. If you open the glovebox, there's THIS label on the inside of the door. It's about 2" x 4" or so. All the codes in the list tell you exactly what your rig has as well as interior and exterior colors. RPO stands for Regular Production Order. I took a picture of mine so I could print it out. As you can see, mine has the LQ4 RPO.