Hi tonytone,
the light bulbs come with the headlamps, the connectors are part of the chassis wiring harness. So I have to fit a 9006 socket to take a 9005 bulb. This just means widening a notch in the connector.
Hi Bxscig, please let me clarify.
GMC Yukon is the short CHASSIS version, Yukon XL is the long version.
With Chevy, Tahoe is the short CHASSIS version, Suburban is the long version.
Denali is the top TRIM LEVEL for GMC pickup trucks and SUV's.
Only the Denalis get the projector headlamps.
They also get the 6 liter engine from the 3/4 ton 2500 models, although they are 1/2 ton 1500 models.
Regular headlamps use 9006 bulbs for the low beam and 9005 bulbs for the high beam.
Denali projector headlamps use 9005 bulbs for both the high beam and the low beam.
The lamp sockets are part of the wiring harness that comes with the chassis.
You will have a small problem if you put a regular headlamp on a Denali, or if you put a Denali headlamp on a regular Yukon.
The sockets for 9005 and 9006 are notched differently to avoid putting the wrong bulb into them.
On my regular, non Denali Yukon the wiring is for 9005 highbeams and 9006 lowbeams.
In order to put 9005 bulbs in the low beam socket keyed for 9006, the socket has to be modified as mentioned 2 posts up.
To repeat, the Denalis use a non standard configuration of having 9005 for the low beams, which normally is a high beam bulb.
Hope this helps. Take care, Eggert
