Couple of questions regarding 5.3

[Firescooby]

I tried search, but wouldn't allow due to "less than 4 letters"

 

I have never owner a GM product. I am thinking of buying a new GMC Sierra ext or possibly 1500 crew cab. It will be 4wd with the 5.3.

 

What kind of gas mileage can I expect driving highway @ 80mph?

 

What's the most miles you guys have heard of on a 5.3?

 

Thanks

[Wingnut]

At 80 mph?

 

About 13 mpg....14 if you're lucky.

 

Go 65, and you'll get 21 mpg with the AC on.

 

These numbers are based on my experience, and MPG seems to vary wildly from person to person on this board....So....YMMV.

[jt1872001]

my total average ,city and highway is 13 the best ever is 17 on highway@like 70 mph

[facn8me]

I am still amazed at the amount of people that buy a full size truck and wonder about gas milage. Please do not take this as a personal attack Firescooby This is just the latest MPG thread. I sort of checked my MPG once. it was around 16. A combintion of highway city and towing. The new 5.3 does have D.O.D (displacement on demand) it is supposed to add 1.5- 2.5 mpg while being unnoticable. for a 21ish highway mpg

 

 

If you are worried about milage buy the hybrid silverado.

[Firescooby]

Ok, thanks.

 

What about the total engine/ truck miles? What could I expect with good maintenance? I use Mobil 1 every 5k and keep up on all other maint.

[facn8me]

I am always leary of first model year runs. I would wait a year on the D.O.D. Just me. Let's the bugs get worked out. Reliability has been great. Maintained I could see 200,00 easily.(surley by then you will want a different one)

[Firescooby]

Well, I'm not buying it for the mileage, but it is important with gas being expensive. Plus, I'm just a poor fireman.

 

I have a one way 65 mile commute every third day. IF I can swing one, I hope to be able to buy a cheap car for commuting. I am a big Toyota fan, so reliability I am used to. I currently have a 2004 Tacoma crew cab, but it only gets 16-18mpg.

 

I had a 2001 F-150 Supercrew and sold it with 12k miles because it had a ton of quality control issues and my wife ad a 2000 Taurus that went through 3 trannies in 82k miles. In other words, Ford is out. Dodge is out unless it was a 3/4+ with a Cummins. I don't like the Silverado front end, but the Sierra is one awesome looking truck.

 

Plus, it would be nice to have a truck that would pull a bobcat when I needed to rent one. I've been having to get it delivered for $75/ pop witht the Taco.

 

Thanks for the opinions.

[foghorn23]

Of the big 3, there's no doubt in my mind as to GM having top spot on gas mileage. I've had 3 GM trucks with the 5.3. Two have had the 3.73 rear end and one a 4.10. I have averaged around 16 with all three trucks in daily driving. (2 lanes, hilly, crooked NC mountain roads) On the interstate with cruse set @ around 68 I could/can get over 20 on all 3 trucks. (I still can't understand how my 4.10 rear end truck did this, but I swear it did.) As far as the 5.3 goes, GM has, of course, had problems with the piston slap issue. Neither of the 3 trucks I've had have had this problem. I really have to say GM has improved their fit and finish since the 99's came out also. My 04 seems to have the best fit and finish of any American vehicle I've owned. I too had an 01 Ford Supercrew, didn't keep it long. I really had no mechanical issues with the truck, but 11-12 MPG was all I could get out of the 5.4 with 3.55 rear end; I've never owned a Dodge (never wanted to) but I understand their mileage is probably the worst of the bunch. Sure as it has been said, you're not going to get CIVIC mileage out of a full size truck, but trust me there's a big difference between 16 and 11 MPG. If you're going full size, I am absolutely sure you cannot beat the General in getting top gas mileage.

 

vroten

[WyRam]

When I drove my Hemi to trade it in from Powell WY to Butte MT I got 14.2 (ave. 74 mph) from Butte to Kellogg ID I got 13.7(ave. 79 mph)My 1500 CC 4.10s on the return trip was 15.4 and 16.25 running the same legs of the trip at the same mph.On a 190 round trip at 72 mph I got 16.75 just before XMas.My around town mileage is 13 to 14 compared to 11 with my Ram and towing the same loads I get 2 to 3 mpg better.

[GLOCKM22]

I drove from Augusta, Ga to Columbia, SC last week. It is about 70 miles on the interstate. I set the cruise control at 71 mph. I got 21.2 mpg. I run Synthetic (Valvoline) oil and a fram air filter. I set the cruise the same on the way back. I got 20.9 on the reurn trip.

[WyRam]

I drove from Augusta, Ga to Columbia, SC last week. It is about 70 miles on the interstate. I set the cruise control at 71 mph. I got 21.2 mpg. I run Synthetic (Valvoline) oil and a fram air filter. I set the cruise the same on the way back. I got 20.9 on the reurn trip.

 

<{POST_SNAPBACK}>

 

 

What gear ratio?

[Mark_in_Tulsa]

On my 2002 ext cab 5.3 Z71 3.73, bone stock with 32,000 miles. I get almost 16 mpg at 80 to 85 mph, when I travel from Tulsa to OKC or Tulsa to Joplin. Both are turnpikes with a speed limit of 75, but the flow of traffic is 80+. But that is on cold weather, I bet in the summer I could get 16+....if I am lucky.

 

My 2004 Dodge ram 4x4 QC Hemi with the 20 inch rims, and the 3.92 rearend gets 15.5 to 15.6 consistantly. But it does weigh a lot more, and has 3.92.

[AG Bill 05 Z71]

I have about 600 miles on a new 5.3 HO. For the past tank of gas with mixed in town and highway driving, I am averaging 16.2 MPG. I keep the speeds at 70 or less....

[robot225]

on my '04 5.3 ECSB Z71 with 3.73s: I average almost 16 at 80 and about 19 at 65-70

[potz1999]

I have about 75000 miles on my '99 5.3, and never had a problem. Who knows about gas mileage, maybe 10-12 mpg on 4.10s, reprogramed PCM, and a very heavy foot. It's a V8 full size truck. If it didn't guzzle gas, it wouldn't be half as appealing.