4.8 Problems?

[MD Chevy]

Alright I am gonna try to explain this as best as possible. I have a 2009 Crew Cab 4x4 with the 4.8. It obviously has the 4 speed transmission. The truck has plenty of power for what I need. The engine only has a little over 7000 miles. I am having some issues in 2 areas. My first area is when I really get on the gas from a stand still. It seems like there is no power until about 1800 rpm's, is this normal? Once it gets there it will run very well. Example my brother and I raced (he has an 09 with the 5.3 6 speed) he beat me like he should, but his truck doesn't have that lag. Maybe I am expecting too much, not a problem just an annoyance and I want to make sure everything is right.

 

My second problem I am almost certain is not correct. Lets say I am traveling down a 2 lane country road that has a posted speed limit of 55 mph. I come to a hill and i just coast down the hill so I don't get a ticket. When I get to the bottom of the hill I slowly put my foot back on the pedal and the RPM's jump about 400-600 and then settle back to the correct RPM for that speed. My 04 with a 5.3 did not do this and I am almost certain it is not correct.

 

Any help in general or anyone with a 4.8 that can help would be a great help.

 

I am anal when it comes to these things and I really hate spending money on something that is not working the way it should (or at least the way I think it should)!

[[email protected]]

Alright I am gonna try to explain this as best as possible. I have a 2009 Crew Cab 4x4 with the 4.8. It obviously has the 4 speed transmission. The truck has plenty of power for what I need. The engine only has a little over 7000 miles. I am having some issues in 2 areas. My first area is when I really get on the gas from a stand still. It seems like there is no power until about 1800 rpm's, is this normal? Once it gets there it will run very well. Example my brother and I raced (he has an 09 with the 5.3 6 speed) he beat me like he should, but his truck doesn't have that lag. Maybe I am expecting too much, not a problem just an annoyance and I want to make sure everything is right.

 

My second problem I am almost certain is not correct. Lets say I am traveling down a 2 lane country road that has a posted speed limit of 55 mph. I come to a hill and i just coast down the hill so I don't get a ticket. When I get to the bottom of the hill I slowly put my foot back on the pedal and the RPM's jump about 400-600 and then settle back to the correct RPM for that speed. My 04 with a 5.3 did not do this and I am almost certain it is not correct.

 

Any help in general or anyone with a 4.8 that can help would be a great help.

 

I am anal when it comes to these things and I really hate spending money on something that is not working the way it should (or at least the way I think it should)!

 

The first power hesitation is normal. The second is also normal, because when you let off the gas, it jumps out of lockup, and when you get back on it, it goes back into lockup. Next time, don't let all the way off the gas and it won't do that.

[dlstewart01]

A tune will cure the first problem...

[MD Chevy]

Is it only normal with the new trucks 4 speeds? The reason I ask is because my brothers 6 speed doesn't do it and my 04 didn't do it?

[MD Chevy]

Yes a tune will, but the main reason I bought a new truck was because of warranty issues. A tune will void the warranty.

[dlstewart01]

GMT800s had some hesitation as well just not as much as the GMT900s. I have never worried about warranty. Just get new PCM/TCM and change them out if you have to go to the dealer.

[MD Chevy]

I agree, i guess it just has to do with having less torque and 3.42 vs 3.73. I can live with that and don't want to take the chance of voiding warranty. If you knew my luck you would understand. Can anyone else agree or disagree with me on my second issue.

[lsuguy]

I say to get a custom tune with Black Bear or a similar company, and get a spare TCM/PCM. That takes care of your warranty issue and first issue for sure. Possibly even your second one.

It is normal for these trucks

[MD Chevy]

How can i guarantee that they cannot trace the tune? That is my biggest fear! I would love to spend a couple hundred dollars and get the benefit, but don't want to get screwed in the end.

[dlstewart01]

Why go through life worrying about things that may or may not happen. you only get one shot at it. Enjoy it...

 

Oh, there are no guarantees with any thing...you pays your money and takes your chances.

[[email protected]]

Why go through life worrying about things that may or may not happen. you only get one shot at it. Enjoy it...

 

Oh, there are no guarantees with any thing...you pays your money and takes your chances.

 

That's good ole' advice from the snake doctor right there! Always spewing with advice to make everyone better.  Believe him, he's a doctor.

[MD Chevy]

Hey I am with you about worrying, but worrying about little things is why we are talking about this. I worry about something going wrong and getting caught is going to cost me a lot, so why even worry about fixing. I am just glad that I am not the only one having these problems. I have never said this before, considering my family used to own the 3rd largest AC-Delco distributer in the country, but I will think long and hard before I buy another GM made truck.

[lsuguy]

There is also a chance you will get struck by lightning when you walk outside. Contact Black Bear Performance. They are a MAJOR vendor on this site. MANY upon MANY users have serviced their vehicles with tunes or with the spare TCM/PCM. Talk to JennaBear . She is a member on here and the wife of Justin, who owns Black Bear. She can give you more info

[[email protected]]

Hey I am with you about worrying, but worrying about little things is why we are talking about this. I worry about something going wrong and getting caught is going to cost me a lot, so why even worry about fixing. I am just glad that I am not the only one having these problems. I have never said this before, considering my family used to own the 3rd largest AC-Delco distributer in the country, but I will think long and hard before I buy another GM made truck.

 

Your truck's perfectly normal. Nothing to be worrying about at all. 

[dcheeseman]

Alright I am gonna try to explain this as best as possible. I have a 2009 Crew Cab 4x4 with the 4.8. It obviously has the 4 speed transmission. The truck has plenty of power for what I need. The engine only has a little over 7000 miles. I am having some issues in 2 areas. My first area is when I really get on the gas from a stand still. It seems like there is no power until about 1800 rpm's, is this normal? Once it gets there it will run very well. Example my brother and I raced (he has an 09 with the 5.3 6 speed) he beat me like he should, but his truck doesn't have that lag. Maybe I am expecting too much, not a problem just an annoyance and I want to make sure everything is right.

 

My second problem I am almost certain is not correct. Lets say I am traveling down a 2 lane country road that has a posted speed limit of 55 mph. I come to a hill and i just coast down the hill so I don't get a ticket. When I get to the bottom of the hill I slowly put my foot back on the pedal and the RPM's jump about 400-600 and then settle back to the correct RPM for that speed. My 04 with a 5.3 did not do this and I am almost certain it is not correct.

 

Any help in general or anyone with a 4.8 that can help would be a great help.

 

I am anal when it comes to these things and I really hate spending money on something that is not working the way it should (or at least the way I think it should)!

 

The first power hesitation is normal. The second is also normal, because when you let off the gas, it jumps out of lockup, and when you get back on it, it goes back into lockup. Next time, don't let all the way off the gas and it won't do that.

 

 

 

 

 

Tyler is right, my 1995 Silverado does this as well as my 2010 5.3 6 speed GMC Sierra. Your truck is fine, no worries. Treat her right and she take care of you!!!