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I just bought a 2017 GMC SLT with the 6.2L and 8 Spd. It had 8700 miles on it. It will idle a little rough at idle momentarily. I only run premium gas, is that normal for the 6.2L? I've installed a Magnaflow 12909 muffler w/o flapper valve and an AFM Momentum CAI. Also, since I've had it, it has a tick that is heard when your standing next to it, or in a drive thru with the window down. Is that normal? After reading on here I'm worried about the afm lifters causing it. I plan on getting a Hypertec programmer so I can change the afm to 70mph and adjust the shifting so it's less clunky. I also will be installing an Elite Engineering EX-2 catch can kit. Will these additions help with the common afm issues? To make it more reliable in the long run? Anyone with experience or knowledge please educate me on this, thank you

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Edited by Coleman71
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Rough idle is normal, ticking is likely from the DI which is normal.

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Hypertechs are a joke.  Avoid and get HP Tuners.

 

I would get a UPR catch can over Elite.  Elite is more popular on this forum only because the owner was more vocal for years.  UPR uses better lines and OEM fittings for less money.  I feel how it is mounted is superior too.

 

Tick is probably the injectors.  These motors are not the smoothest at idle. 

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Also, you can't tune the 8 speeds unless you buy an unlocked tcm.

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I just bought a 2017 GMC SLT with the 6.2L and 8 Spd. It had 8700 miles on it. It will idle a little rough at idle momentarily. I only run premium gas, is that normal for the 6.2L? I've installed a Magnaflow 12909 muffler w/o flapper valve and an AFM Momentum CAI. Also, since I've had it, it has a tick that is heard when your standing next to it, or in a drive thru with the window down. Is that normal? After reading on here I'm worried about the afm lifters causing it. I plan on getting a Hypertec programmer so I can change the afm to 70mph and adjust the shifting so it's less clunky. I also will be installing an Elite Engineering EX-2 catch can kit. Will these additions help with the common afm issues? To make it more reliable in the long run? Anyone with experience or knowledge please educate me on this, thank you
20181224_064440.thumb.jpg.22e346c122b6dc648ae25572dd38b966.jpg


Congratulations. Great looking truck. The ticking sound when standing outside is normal with the 6.2 and 5.3.


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Sounds normal, mine is at 8600 mi.  Mine shifts smooth and always has other then sometimes a little harsh on the downshift while slowly  climbing my driveway incline. The trans is not tuneable in the 17-18' , 8 speeds without sending in the TCM.

I would also recommend the UPR catch can, really nice plug & play OEM fittings and simple hookup and mounting. Takes like 10 minutes to be up and running.

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Rough idle is normal, ticking is likely from the DI which is normal.
Thank you, since I didn't buy it new, I wanted to make sure

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Hypertechs are a joke.  Avoid and get HP Tuners.
 
I would get a UPR catch can over Elite.  Elite is more popular on this forum only because the owner was more vocal for years.  UPR uses better lines and OEM fittings for less money.  I feel how it is mounted is superior too.
 
Tick is probably the injectors.  These motors are not the smoothest at idle. 
Ok, I'll look into those, thank you

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Congratulations. Great looking truck. The ticking sound when standing outside is normal with the 6.2 and 5.3.


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Thank you

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Sounds normal, mine is at 8600 mi.  Mine shifts smooth and always has other then sometimes a little harsh on the downshift while slowly  climbing my driveway incline. The trans is not tuneable in the 17-18' , 8 speeds without sending in the TCM.
I would also recommend the UPR catch can, really nice plug & play OEM fittings and simple hookup and mounting. Takes like 10 minutes to be up and running.
Ok good to know, I'll look into the upr. Thank you

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Hey aside from the tick you may also hear something that sounds like chickens LOL...I have a UPR can for a 5.3 and just got one for a 6.2. You will love the fit (except needing to enlarge the mounting hole) and finish. Very quality piece. I went with an Elite CSS as it was priced right and a good piece.

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Yep, ticking noise is normal. There are 3 very good cans out there and you will be happy with any of them, UPR, Elite and RXP. I run the RXP and run the UPR valve cover bridge line because of the looks but used Elite's pictures when mounting mine...

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1 hour ago, 3tspapat said:

Hey aside from the tick you may also hear something that sounds like chickens LOL...I have a UPR can for a 5.3 and just got one for a 6.2. You will love the fit (except needing to enlarge the mounting hole) and finish. Very quality piece. I went with an Elite CSS as it was priced right and a good piece.

I'm going back and forth between the Elite and a UPR. I like the stock syle connections of the UPR, but the mounting option (Spare battery box) of the Elite. I'm leaning toward a dual valve setup to catch as much as possible. Any thoughts on that?

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1 hour ago, SS502 said:

Yep, ticking noise is normal. There are 3 very good cans out there and you will be happy with any of them, UPR, Elite and RXP. I run the RXP and run the UPR valve cover bridge line because of the looks but used Elite's pictures when mounting mine...

I'm going back and forth between the Elite and a UPR. I like the stock syle connections of the UPR, but the mounting option (Spare battery box) of the Elite. I'm leaning toward a dual valve setup to catch as much as possible. Any thoughts on that? Sorry, should have replied to yours and 3tspapat in the same reply.

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