Gmt900 Speaker Fit

nashss · November 1, 2011

07 Silverado front speakers cut out and need replaced. Looking online on crutchfield and such looking to see what I want to put in my truck and seeing a couple sizes from 5 1/4 to 6 3/4 so whats the best fit. I want a 6 1/2 or a 6 3/4 for the best sound but not sure what the factory size is or what would fit without much problems. I need the front first but would eventually like to do the rears as well but at a later date. Any help would be greatly appreciated. Thanks.

jimbrown1 · November 1, 2011

The crew cabs and extended cabs have different size speakers (I believe). I just replaced my crew cab door speakers (both front and rear) with 6.5" Boston Acoustics. The front doors have component system since there are separate tweeters in the A pillars.

ChevyTech77 · November 1, 2011

Same size speakers will fit ext cab rear doors as the crew cab rear doors the simple fact is that if you have an ext cab, you'll have to make your own adaptor plates to mount the speakers because nobody else does and it's a completely different opening than a crew cab is. Just played that game in the last month, not fun.

JokerJ · March 8, 2012

It's disappointing that no-one has made a bracket for the NBS ext cab speaker. It's design that's 5 years in...WTH?

ChevyTech77 · March 8, 2012

It's disappointing that no-one has made a bracket for the NBS ext cab speaker. It's design that's 5 years in...WTH?

I agree but I think the simple fact is that most people replace the front door speakers and A pillar tweeters with a component system and then completely ignore the rear door speakers. I'm sure you could probably cut the factory speaker out of the factory adapter and get like a 5-1/4 or something to fit in there but yes, still senseless that nobody builds an adapter.

holty · March 8, 2012

Just making sure i'm reading this correctly, there is no direct replacement for the Extended cab REAR door speakers, but there are direct replacements for the crew cab trucks, correct? (Strictly speaking of GMT900 NNBS)

The OP was asking about FRONT speakers, am i reading this thread wrong, or are you guys saying that the FRONT speaker sizes are different for Extended cab and crew cab trucks too?

redjewel2ss · March 8, 2012

front speakers are the same in both cabs. 6 1/2 or 6-3/4 speakers fit in the adapter that mounts to the front speaker.

i've been tossing around cutting out my rear speaker to direct fit an aftermarket one, just haven't found the time to take the door panel off for measurements.

IF i ever do, i'll document my work so others can attempt the same thing.... this might be my excuse to finally get that dremel tool i want.

ChevyTech77 · March 8, 2012

I have some pictures of the ex cab door speaker mounting openings AND my factory speakers all pilled up in the garage. Maybe I should get my lazy behind out there this weekend (now that it's 70 degrees in March, in Michigan) and do some cleaning along with taking some pictures and measurements for you peeps.

I'll tell ya what, I'll try my best.

And yes, the front doors all take 6-1/2" speakers. 6-3/4" fit but the 6-1/2's fit better imo.

holty · March 8, 2012

Thanks bud!

JokerJ · March 8, 2012

I cut a template out of MDF before the freezing weather hit Va Beach . Actually, I didn't have a router to make the cuts for the door and speaker. I've since obtain a dremel with routing capablility and will attempt it again. When I feel like farting with the door panel again.

508gm1 · March 10, 2012

Hi

2011 Sierra 1500 Extended cab. Here are pictures of the brackets I just made for mine.

Front - 6.5

Rear - 6X8

I modified the factory brackets. The rear ones were the most work. I spent about 2 hours with the dremel. This left hardly any plastic left, so I rivited a 3/16 aluminum plate over top of it for strength, then siliconed the 2 together. The 6X8 speaker just barely fit. There is also a piece of rubber measuring about 3/16 between the aluminum plate and the speaker itself. If I had to do it again I would have made the aluminum plate about 1" longer to extent past to bottom of the plastic bracket.

Cheers, Brendan

508gm1 · March 10, 2012

Here are pictures of the factory rear speakers in the extended cab.

They measure appx. 6 5/15 X 9

I replaced these first, and the sound improved alot. All that muddy sounding bullshit was gone.

Cheers, Brendan

ChevyTech77 · March 12, 2012

Beat me too it.

Nice adapters!

redjewel2ss · March 12, 2012

Here are pictures of the factory rear speakers in the extended cab.

They measure appx. 6 5/15 X 9

I replaced these first, and the sound improved alot. All that muddy sounding bullshit was gone.

Cheers, Brendan

i found the problem with these, they're made in Mexico, not China

thanks for the pics. now i have a better plan of attack! i think i'll do what you did with the aluminum plate, except use a 5-1/4" speaker so it'll fit in that round hole without trimming so much.

is there any trick to removing the stock rear speakers? the thing at the top on the back of the adapter looks hard to get the speaker out.

ChevyTech77 · March 12, 2012

One 10mm bolt, then pull towards you until it unclips from the door, then pull up to unlatch the bottom of the speaker from the door. Almost identical to how the fronts are held in.