4.8 question

[galeo7171]

I just bought an 08 tahoe LS with the 4.8 engine. I didn't know that there was an option to get the 5.3 until two days after I bought it. I guess I should do more research next time.... my question is how much difference in power is there between the two motors? My tahoe has the 3.73 axle ratio if that makes any difference. Also, how reliable are the 4.8s? Anyone have one and regret not getting the bigger motor?

 

[Gambler]

I've heard the 4.8s can be a little more sluggish. But on the other hand you'll get better gas mileage

 

[emann_01]

actually the 5.3 gets better gas mileage

they get the same in the city but the 5.3 gets better (i think 1 mpg) on the highway

bigger engine = more power= less work to keep this big bastard moving down the road

 

[galeo7171]

actually the 5.3 gets better gas mileage

they get the same in the city but the 5.3 gets better (i think 1 mpg) on the highway

bigger engine = more power= less work to keep this big bastard moving down the road

I noticed that hp ratings for the two motors is rougly a 25 hp difference. How much hp can I add to the 4.8, and whats the best way to do it? If I would have known about the 5.3 I might would have got that, but the 4.8 seems to be a fairly quick motor.

 

[73shark]

How much difference in torque between the two engines? Torque is what gets you going.

A blower will add the most hp but is pricey.

 

[galeo7171]

the 4.8 has 305 lb-ft and the 5.3 has 340 lb-ft. I don't know how much of a difference this makes..

 

[73shark]

It's about 10% less plus with the infamous torque management, it will probably feel a little anemic off the line.

BTW welcome to the Tahoe Forum.

 

[galeo7171]

It's about 10% less plus with the infamous torque management, it will probably feel a little anemic off the line.

BTW welcome to the Tahoe Forum.

Thanks for the welcome. I traded in my 06 quad cab 4x4 dodge ram with the 4.7, and the 4.8 seems to be quicker than the dodge. Overall I'm pretty happy with teh 4.8! I'm guessing a programmer of some sort will help out with the hp and torque? Does the 5.3 and 4.8 both have torque management? anything to do to get aroun that?

 

[Black Dog]

A custom tune cane reduce the TM, as well as optimize the rest of it for you. Also, I understand that the 4.8 is well suited to supercharging, I think related to lower compression ratio and/or shorter stroke.

 

[badassstang90]

I just purchased a new Hoe with the 4.8 and also have a dodge ram with the 5.7 hemi. Of coarse the hoe feels down on power, but It rides so smooth and seems to get solid gas mileage. I will be looking at doing some mods shortly. I am very satisfied with the purchase, and proud to be a first time GM owner.

 

[PaulC]

I live near the Poconos, which means that if I'm not driving uphill, it's because I'm driving downhill. Prior to my Tahoe, I owned a Ford Expedition with the 240 hp 4.6 liter V8. I never confused it for a rocket, but it got the job done. The only time that I noticed a power deficiency is when I was trying to fly up a long interstate hill at a relatively high altitude, which caused the trans to hunt between 3 & 4 gears. My cure was to lock out 4th gear during these events and slow down a bit. Not a big deal.

OTO, on the day I traded my Expy for the Tahoe 5.3, I felt like a guy who traded a Malibu in for a Corvette.

 

[ventu71]

The 5.3 will get better mpg because it has active fuel management, the 4.8 does not. A power programer or custome tune is the cheapest way to go for a modest power increase, you can expect to gain 8-18 hp with that alone. If you want more power then a blower or camshafts will do the trick, but your mpg´s will come down in a hurry

 

[emann_01]

The 5.3 will get better mpg because it has active fuel management, the 4.8 does not. A power programer or custome tune is the cheapest way to go for a modest power increase, you can expect to gain 8-18 hp with that alone. If you want more power then a blower or camshafts will do the trick, but your mpg´s will come down in a hurry

be careful about your comment about the blower reducing mpg....with your foot not "in it" you will actually increase mileage because you burn fuel more efficiently

 

[Repoman05]

I just bought an 08 tahoe LS with the 4.8 engine. I didn't know that there was an option to get the 5.3 until two days after I bought it. I guess I should do more research next time.... my question is how much difference in power is there between the two motors? My tahoe has the 3.73 axle ratio if that makes any difference. Also, how reliable are the 4.8s? Anyone have one and regret not getting the bigger motor?

I just bought an 05 Tahoe w the 4.8 2wd but has a 6" suspension lift w 35x12.5x20 s.. extreme slug. But I'm not a mechanic by trade but know a little bit about a lot. I do know that even tho its a slug off the line after you hit 30mph it doesn't lack for power. Like I said. Its got 35" tall tires and it has no lack of power. The 4.8 is bullet proof... extremely strong motor. My one issue it the torque management. Which ...yes I know is to save the transmission but.....come on... As for your question about gas mileage ..not so hot.... durability ...strong engine... Right now I am attempting to either turn TM off or change so I can at least turn a tire in the grass.

 

[ccapehart1017]

im happy with my 4.8 little sluggish on the take off but that because of the 4 speed autotrans it has higher gear ratios so it halls ass 75 80 it tends to get away from you to if you got a heavy foot