NAV and 6 disk changer in a Silverado

[masterp2]

Sorry for the late arrival!

 

What is the head unit Linda? What vehicle is it stock on? Any other threads where I can learn more about it? Can't search for Um8 because it is less than 4 char long. Michael

[linda]

The head unit is the actual radio itself. Your Head Unit (HU) is a sindle disk cassette radio. My new head unit (HU) is a UM8 Navigation radio. Its just a technical term for radio i guess. What you need to do this install is the correct changer (model number #15055250) and the harness (model #15312903). The changer can be found on Ebay all the time...like this one:

 

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...item=2465444560

 

The harness costs about $20 and by changing a couple of wires in the harness its a pretty easy install. When you get you stuff ready, i will walk you through it, or poonis can help you now too. His install turned out real well.

[masterp2]

I'm sorry, I should have asked, what is the UM8 Navigation radio, features etc. what vehicles is it stock on? You have said it sounds better than the original, why do you think that is? You still have the bose amp and speakers?

 

Great job by the way. I latched onto this, as I was referred to this thread with a desire to do the CD changer as well.

 

Michael

[linda]

the (RPO UM8) NAV radio is an option on the yukon Denali's and Cadillac escalades. Yes i still have a BOSE AMP, but its the Luxury BOSE upgrade AMP, not the one that comes in the chevy line-up of vehicles, its the one that comes in the Yukons, and Cadillacs. Its all the same connections, just unplug then old AMP and plug in the new one, as well as making a few very minor wiring changes in the AMP harness (no cutting, just wire swapping). The difference in sound is very obvious, first you get an added "midrange" option to adjust, in addition to the "bass" and "treble" options. Then you get "sound field" options.....such as "spacious", "driver", "passenger", and rear seat, sound field options. Lastly, you get an ambient noise adjustment. So when the cabin volume sounds change, the audio levels change. If you were driving on a gravel road where there might be more bass sounds in the cabin from running over the stones....the bass levels in the audio would automatically increase to compensate for it. Plus it just sounds a lot more rich and full, I would believe there is a wattage increase as well, but im not sure about that.

[bigdogs]

I didn't know there were 2 different Bose amps on the GM vehicles. I take it then you can't use the Bose amp from the Sierra but need to change to the luxury one?I'm not even sure where the amp is located on this truck.

[linda]

Ext. cab and crew cab models have the AMP located under the storage compartment in the console. Reg cab models have it under the dash someplace i believe. Yes, you need the luxury AMP for any GM vehicle that you want to put the Navigation radio in.

[masterp2]

I would recommend buying a PAC adapter for the bose harness, then you can use any amp you want.

 

Paying for a Bose OEM amp is a waste of money, JMO, far better sound is available, though preserving the factory look is a plus, and possible with this arrangement. This can be done while bypassing the bose (mystery) amp. I may be wrong, but if you do intend to bypass the bose amp, you do not have to replace it if you are willing to run a higher quality amp on line outputs provided by the PAC adapter. Ooops, sorry, you are correct, the lux Y91 bozo amp is needed for the Nav upgrade. The GPS won't work w/o it. Soon there is going to be a NAV unit compatable with the existing non-lux amp, so I here.

 

Linda, again, nice work. If you don't already have it, you can add the PAC adapter without changing a thing, for the purpose of getting some real bass (sub box), something Bose is completely unfamiliar with.

 

But while these Nav units are fetching $1500 on EBAY, it will never be safe in my driveway. Nonetheless, it is tempting, I would buy one at the right price.

[linda]

well masterP, as much as i agree with you on the BOSE issue.....in this situation it is imperative that the NAV unit run in conjuction with the BOSE AMP, no exception. The 2003 and newer GM vehicles use a Class II data wire through out the system including the BCM. This is very similiar to a LAN cable or network cable. There is info that is constantly being transfered through out the sound system (HU, AMP, BCM) that is needed to keep certain functions operating normaly. While a PAC adapter will help to retain continuity of the LAN and other trivial functions like auto dimming, and door chimes, i dont think it will be able to comprehend the more important data transfer like VSS (vehicle speed sensors), ambient noise volume, and sound field options between the UM8 and the BCM. It is true that BOSE is not the best option for audio performance in the GM vehicles, and a better AMP and a SUB box would sound a hell of a lot better..........however, the Y91 upgrade BOSE AMP does sound 10 fold better than the stock chevy BOSE AMPs, and i love having a factory look with my navigation HU. If you went with an aftermarket NAV unit, then the sky is the limit i would guess, you could use any AMP, speaker, adpter combo you wanted.

[poonis]

PAC adapters are great for replacing the stock with an aftermarket units or adding more AUX inputs, however, the rear dvd and audio controls will not work with PAC adapters for 03 and up (so I heard). And I really like having rear controls in the back and having the feature to let people in the back listen or watch something else while I listen to what I want in the front.

[bigdogs]

Thanks Linda. I didn't know I would have to replace my Bose amp with the luxury one. I wonder what the difference is between the one I have on mine compared to the other one.

 

I agree that Bose may not be the best name but like you said if you want it all to work I think you are stuck with it. I still would like to add XM and that does require a third party adapter and Pioneer tuner.

[linda]

you can find them (luxury AMPs) on Ebay quite often....i payed $40 for mine. If you can find all the right parts, you can add a gm factory XM system to the truck without using adapters.

[bigdogs]

Thanks Linda, will keep that in mind about the new amp. As for XM I saw one NAV unit that claimed it was "newer" and had the XM tuner built in. I'm not sure if/how true that is. I'd much rather go with a factory setup to keep everything working with each other.

[masterp2]

That is good to know Linda, I did wonder about amp continuity being relevant.

 

Poonis, I am describing a PAC adapter (there are many) specifically for adding amps (presumably to add a sub) that provides a clean line voltage signal. I'm sorry I through everybody off when I mentioned FM modulation (I should have said "LOC"), too many beers. FM modulation has nothing to do with it. Presently the only good way I know of to provide a clean signal for bass drivers. The adapter would keep the integrity of the data bus and preserve its features, adjusting the output volatage as a function of the head circuitry.

 

I stand corrected on the bose amp requirement, I believe you, Linda, and appreciate not getting slammed, very tactful.

 

When I posted that I was pissed, I had closed the deal on a changer on EBAY and the idiot went and sold it to someone else, despite our deal. LOCO.

[masterp2]

Linda,

 

"AUX harness------------#15312903---------------------------$25"

 

Is this for the changer? Is it the same harness for the stock radio? I am assuming you found no changer harness behing the dash.

 

Michael

[poonis]

I am describing a PAC adapter (there are many) specifically for adding amps (presumably to add a sub) that provides a clean line voltage signal.

I'm not too familiar with the PAC stuff. Do you know if PAC works well when adding aftermarket amps? I'm just wondering because I'm thinking about adding more power.