Stupid question...cab lights?

[Darel]

What exactly is the point of cab clearance lights? Are they somehow for use by the driver or low-flying aircraft?

At least they look cool.

Darel

 

[hammersley]

It's my understanding that trucks which are over a certain width, in our case the 3500 dual wheeled rigs, are required to have them as a safety isses. This is to alert other drivers, that the oncoming vehicle is wider than perhaps the headlights you see... so one doesn't get to close in a tight situation, narrow bridge etc..... Somebody else may have the NHTS reg on it... ...

 

[Darel]

But I've got a 2500...

 

[DieselDoghouse]

IBID on the prior explanation, my understanding is the same. The standard is 2 outer or 'clearance' lights and 3 grouped 'classification' lights to identify the extra width. They are offered on our 'littler' trucks because they are 'cool'. BUT, they do serve a great purpose - in hilly or washboard terrain they can announce your approach over a hill before your headlights are visible - keeping you from being high-beamed or getting the guy who was about to pass in your lane back into his!! In this era of extra light for safety , roof lights can be an added benefit. Cab lights are one of the first things you see in bad weather in hilly country!

 

[Hammer]

PLANE INCOMING !!!!!!!!!

Thats me,,Low flying aircraft here,,Been told by some the way I drive I should have a pilots liscense,,All I do at that point is this,,Reach into my wallet and break out mt NHRA liscense and tell them here it is,,Physical is a FAA type three to get it so I have it,,Flame Red flight 101 now boarding,any takers???,,,, Yes I do have a few screws loose too... ...

 

[illflem]

Shoot, an' all this hyar time me thunk they were jest their t'look perdy.

 

[NETim]

clearance lights

Seems to me though that I've seen 3500's w/o the lights on the cab. I know that 3 red lights center rear are required for over 80 trailers and vehicles, but not clear on the cab lights.



Tim

 

[Shovelhead]

Next time you pass a truck scale, look for the measuring sticks (both for truck height, and length).

The lights are required on BIG trucks so the scalemaster can see the height, length, and width of the rig even at night.

 

[DennyDay]

Cluster lights

The three lights, amber front and read rear are required on any vehicle 80 or more inches wide. the 2500 does nor require them unless towing a trailer over 80 inches wide. This includes goose necks where there is no way to install lights on the front of the trailer, but must be on cab of towing vehicle.



See CFR49, 393. 11, USDOT Safety Regulations



Hope thius answers question,

Denny

 

[Joe G.]

The maximum width in the service manual for our 2500s is 79. 4". I wonder why that is?

 

[illflem]

Joe, it probably has to do with the rear axle rating. I doubt if a wider flat bed would effect it but extending the wheels out on the axle could.

 

[Joe G.]

Bill,



The comment was about DC building the truck as wide as possible without having to put cab lights on it. I little wided and they would have had to put the lights on our 2500s.

 

[illflem]

Does that mean a 2500 might need cab lights if it has fender flairs?

 

[Joe G.]

Yeah, if someone ever stopped to measure. I think you would REALLY have to irritate some cop for that to happen!

 

[Okie-Go]

I may be crazy but seems to me fewer people will pull out in front of you at night with them on. I guess they can't tell how big of a truck it is. They do look good also.

 

[Extreme1]

CD Day is right on the money. ALL 3500 trucks have the clearance lights and the tailgate cluster.

 

[BigDaddy]

As C. D. Day explained, the additional lights are a DOT requirement for vehicles 80 or more inches wide. I have the cab lights installed to increase vehicle visibility. With the 4 in. exhaust they can better hear me, and with the additional lights they can better see me.