5.3 .... whats your best MPG
 

My 2004 Sierra has 210,00 miles, 5.3, and a BAKFlip G2 Tonneau Cover

Next will be Dual Exhaust.

On a trip to Louisville I got 19.3 mpg. Not bad.

What's your MPG.

Re: 5.3 .... whats your best MPG
 

Subbed

Re: 5.3 .... whats your best MPG
 

My 02 4wd subruban with 293,000 has done 16 on a freeway trip.

Re: 5.3 .... whats your best MPG
 

Short bed reg cab 2 wheel drive 5.3 I keep getting 16.5 or a lil better in the city even with being heavy on the pedal
Such a fun truck

Re: 5.3 .... whats your best MPG
 

I am thinking if I add Dual Exhaust I might reach 20 mpg

Re: 5.3 .... whats your best MPG
 

My 99 4wd got 16-17
My 13 4wd gets 16-17
My C30 6.0 gets 16-17..

Re: 5.3 .... whats your best MPG
 

I need to see what rear axle I have... :metal:

Re: 5.3 .... whats your best MPG
 

My guess would be you have a 3.42 or 3.23. The duals should help, unless your like me and you push down harder cause the truck sounds so much better. :D

Re: 5.3 .... whats your best MPG
 

Look for the G prefix codes on the SPID. Those will tell you what gears GM installed in your truck.

Re: 5.3 .... whats your best MPG
 

Is there a place that ID's the numbers...

Re: 5.3 .... whats your best MPG
 

GU4 - 3:07
GU5 - 3.23
GU6 - 3.42

If you got another hollar, and I'll look it up.

Re: 5.3 .... whats your best MPG
 

Thanks :metal:

Re: 5.3 .... whats your best MPG
 

05 5.3 2wd extended cab 200+ miles avg 16-18 in town on highway about 20

Re: 5.3 .... whats your best MPG
 

Yesterday I drove from Nashville, TN to Gulf Shores, Al , traffic wasn’t too bad , not too much stop and go. My 2018 Silverado, crew cab ,5.3 , 3 people, luggage , running 73-79 , I averaged 25.5 mpg .

Re: 5.3 .... whats your best MPG
 

WOW :burnout::burnout:

Re: 5.3 .... whats your best MPG
 

What the?

Re: 5.3 .... whats your best MPG
 

My 2005 SWB, 5.3, 2WD, has the trailer towing option. Has 3.73 gears, locking differential. Has done 20 MPG several times. Bone stock. I like it!!!

Re: 5.3 .... whats your best MPG
 

2008 Envoy Denali (not the XL), still has AFM active, best I've gotten was 21 highway. 4x4 3.42 gears, G80 locking diff

Re: 5.3 .... whats your best MPG
 

I know this isn't quite the same since it isn't in a truck. But I have a 2000 5.3, no egr, 6.0 manifolds with 2.5" exhaust and super 44s, BTR Stage 3 cam, Super T10 and 3.08 gears. It gets 22.5mpg driving a mix of hwy and stop light traffic daily driving it.

Re: 5.3 .... whats your best MPG
 

GT4 G80

So do I have a 3:07 with Posi?

Re: 5.3 .... whats your best MPG
 

I bet that Camaro is a whole lota fun too

Re: 5.3 .... whats your best MPG
 

I think I finally figured out how to attach a photo . This was from my trip last week , 25.5 mpg .

Re: 5.3 .... whats your best MPG
 

What truck and what year?

Your dash doesn't look like my dash?? Looks like a new generation.

Re: 5.3 .... whats your best MPG
 

From what I have read, GT4 is a 3.73- G80 is a Gov Locker. A nice combo.

Re: 5.3 .... whats your best MPG
 

Thanks :metal: