Late cab light question...

[esbstuff]

When did GM do away with the welded nuts for the cab (roof) lights. My 87 had nuts and this 89 does not... I checked the SPID and cab lights were factory installed. The roof shows no obvious signs of replacement, but I will check further... First thought was GM was trying to use up roof skins and drilled the holes themselves.

[mrolds88]

My 77 doesn't have nuts for the clearance lights either. It had these stupid little j clips. I'm replacing them with rivnuts.

[Keith Seymore]

Does the cab have any kind of nut or were the screws just threaded into the roof skin?

I suppose it is possible they missed that this specific truck got roof lights and drilled them in repair.

K

[esbstuff]

Originally Posted by Keith Seymore

Does the cab have any kind of nut or were the screws just threaded into the roof skin?

I suppose it is possible they missed that this specific truck got roof lights and drilled them in repair.

K

The screws were just screwed into the roof. All 5 were the same. It had the corresponding sheet metal screws vs the machine screws as the normal was... The bed had the hole for the tailgate lights too. Paint everywhere it should be, so the problem was caught before paint. The truck did not come with the gate, so I am at a loss there.

[80SPORT]

I checked a couple of our yard trucks....the 77 was threaded;the 81 was threaded;the 86 reg cab and 88 crew just had sheet metal screws.All are original paint.It could vary by year or even by plant.

[v30crewcab]

my 88 is just screws into the metal.

[Keith Seymore]

Sounds like it was an intentional change for the later years (probably a cost savings).

K

[chengny]

Some images showing what comes in the pack containing a complete OEM marker light set (minus the harness). If you look closely at the installation/layout sheets you can see that it appeared to be a body style issue rather than the model year that determined whether speed nuts were spec'd (used machine screws)- or if the lens were simply fastened by sheet metal screws driven right into the skin of the roof:




The package included all the hardware required to do the installation either way:

[80SPORT]

My early factory original units appear to have a special area embossed into the roof panel and the nuts(which take a 8/32 ss machine screw) welded in.
So I assume this was a spec panel for the roof marker lights.The later trucks appear to have just the hole punched and use sheet metal screws.Not sure if the factory built units with speed nuts as per the service kit.Interesting to see the engineering detail including the special sealing washers that went under the screws;I am using o rings now under the screws to seal as I was unable to source new washers.Roof marker lights were standard on R05 duallys and available on most other models -but not with Z77 Chevy Sport.They also show as available on Suburban ...but I can't remember seeing one with them.

[Anchorism]

Originally Posted by chengny

The package included all the hardware required to do the installation either way:

So..... where did you come across such a nice complete kit?

[esbstuff]

I forgot to post that the truck in question is/was a 1989 R30 crewcab dually.

Yes its a 'R05' truck.

[esbstuff]

Originally Posted by 80SPORT

My early factory original units appear to have a special area embossed into the roof panel and the nuts(which take a 8/32 ss machine screw) welded in.
So I assume this was a spec panel for the roof marker lights.The later trucks appear to have just the hole punched and use sheet metal screws.Not sure if the factory built units with speed nuts as per the service kit.Interesting to see the engineering detail including the special sealing washers that went under the screws;I am using o rings now under the screws to seal as I was unable to source new washers.Roof marker lights were standard on R05 duallys and available on most other models -but not with Z77 Chevy Sport.They also show as available on Suburban ...but I can't remember seeing one with them.

I had a 1/2 4x4 Bonanza truck that had factory cab lights too. (Nuts in the roof skin.) But no tailgate lights.

[chengny]

So..... where did you come across such a nice complete kit?


Ah haha - that's funny. I don't have the actual kit I just have the pictures of it.

The pieces can be bought ala carte here:

http://www.gmpartseast.com/gmc/compo...m40k30903.html

Do get too excited though; GM Parts East actual inventory often does not reflect what they list on their site. To their credit however, they are much better most internet vendors of vintage GM parts. And they email you (usually within a day) with a list of which parts you ordered - the ones that they can actually supply.

[Anchorism]

whew... not cheap though thats for sure. Theyre close to $90 a light! Thats if you go with the whole shebang.

[mrolds88]

And did you notice that they have 2 different #s for the lenses? Federal and Californie. guess they must be part of the emissions equipment now. LOL

[80SPORT]

Originally Posted by esbstuff

I had a 1/2 4x4 Bonanza truck that had factory cab lights too. (Nuts in the roof skin.) But no tailgate lights.

As far as I know the tailgate lights were mandatory on all R05 dually pickups ....and not available on anything else.

[Anchorism]

Originally Posted by mrolds88

And did you notice that they have 2 different #s for the lenses? Federal and Californie. guess they must be part of the emissions equipment now. LOL

Probably a later dated requirement and they probably have some with california requirement codes on them.

[Keith Seymore]

Originally Posted by 80SPORT

As far as I know the tailgate lights were mandatory on all R05 dually pickups ....and not available on anything else.

Anything over 80" wide requires running lights. There were some one ton single wheel 4x4 combinations where the front axle width drove the tailgate and cab lights.

K

[Keith Seymore]

Originally Posted by mrolds88

And did you notice that they have 2 different #s for the lenses? Federal and Californie. guess they must be part of the emissions equipment now. LOL

At the time California regs did not allow any Amber light to be visible from the rear, so the California only lens had black paint on the rear portion; the Federal lamp was completely Amber.

Tying them to the emissions package was just an existing and convenient way to make sure they got to the right state.

K

[Keith Seymore]

ttt