Side marker "lenses", what's the deal?
 

I would like to ask for some guidance about my 69 CST/10 please. My goals is to get the truck mechanically sound but leave the outside as-is as much as practical (for now).

For the Texas state inspection, a mechanic who does inspections let me know all reflectors must be crack free to pass inspection, and he pointed out that mine are deteriorated and cracked with age.

When I look them up to buy some, they are called side marker lenses. I was wondering why they are called lenses instead of reflectors, so I took them off. The front one came off in 2 pieces and the inside of the holder looks like it has an indentation. The back one came off all in one piece with the holder.

What is the deal here? Are the lenses used whether or not there are lamps behind them? I'm confused by what I see offered online for replacements, because some come with a holder that has a cross-shaped hole in the back, but there is nothing that looks like it would hold a light bulb. Mine just has a round plastic surface, no hole. I also find some that look like 2 horizontal bars, with or without chrome trim, and those are quite different from what I have. So, I don't know what exactly to get. I don't know if I want to light these up, I don't have wiring that goes to the holes where they mount. At this point I would just like the truck to pass inspection so I can get it registered.

If I did get the whole assembly with the cross shaped hole, and I wanted to add a lamp to it, what sort of holder would hold itself in that cross-shaped hole? If I started out with unlit markers, would I just cover up the hole to keep water, dirt, and bugs out? Example of new one I see offered is the last picture I posted below.

Re: Side marker "lenses", what's the deal?
 

I was a Texas inspector for several years. If it's just a reflector I don't remember anything in the book about it. If it had a light behind it, it can not show any white light through the cracks. If it doesn't you're good to go, but it does have to be the correct color. If it's faded you might just try a colored bulb. If he didn't charge you the inspection fee like they are required, you might just try some other station

Re: Side marker "lenses", what's the deal?
 

I did not get an inspection yet, this was just a visit from a relative of a neighbor and we were talking about the truck. Perhaps he is overly meticulous and if I avoid his station I will be fine. I don't have anything I would call cracks, but he was calling them cracks. It is on the surface and I suppose I would call it aging and crazing. No white showing through from lights behind, it was only the actual reflector surface he was talking about, not the lense areas of the plastic with light bulbs behind. I have more stuff to do to fix things that are definitely broken, such as the dimmer switch, intermittent headlight switch, horn is dead, mirrors rusted off, parking brake pedal seized with rust, etc. so I will work on those things first.

Re: Side marker "lenses", what's the deal?
 

I would call you good on the side marker lights and let you go if it was me unless some law has changed since 2008 when I was last licensed. Good luck to ya

Re: Side marker "lenses", what's the deal?
 

Thanks very much. Perhaps that is another $100 I don't need to spend right now (4 side and 2 tail lense/reflectors). It looks cosmetic to me.

Re: Side marker "lenses", what's the deal?
 

You're welcome. Hope it works out for ya

Re: Side marker "lenses", what's the deal?
 

This may answer some questions...

My 69 CST came new with markers like yours (see 1st picture below). They have a reflector at one end and a lens at the other end without a light and just a raised circular area on the back (where a light provision would be provided later on). The lens and reflector portions were, in fact, separate pieces (see picture 2). I noticed soon after I purchased the truck that other CSTs I saw had lighted deluxe side markers (those with the horizontal bars and stainless trim). Thinking I got ripped off, I contacted Chevrolet. They advised me that my truck was produced the 2nd week of December,1968, and that the lighted markers were not used until a couple weeks later. The non-CSTs got lighted standard markers like yours but they were modified to accept lights. The third picture shows the bulb holder used with lighted markers of both types. The holder is installed and turned a fraction of a turn to lock it in place.

It appears your truck was an early model year build that would have had the standard markers without lights and that the lens and reflectors on one are no longer adhered to the housing..

Re: Side marker "lenses", what's the deal?
 

maybe hes trying to do you and others on the road a favor by being maticulous. in the aviation industry its called being safe. If he called you out on it and you went somewhere else thast your bad not his. sort it out and fix what needs fixing. He's doing his job and there are legal ethical and moral responsabilities that go along with it. New lenses cant cost that much. they look better too. cumon' now, spend a little coin on your hobby

Re: Side marker "lenses", what's the deal?
 

My 69 has the same front reflectors. Were the rear/red lenses the same, just reflector? My bedsides were pretty wasted in that area. Wife harness was too rough to give clues too I am far from that on the truck still. This thread made me think of it again

Re: Side marker "lenses", what's the deal?
 

I'll have to re-trace the research on this subject, but the issue was caused by federal regulations and lobbying to change the time frame of their implementation.
The car makers typically would implement coming changes in the model year prior to the requirement coming into effect.
FMVSS108 is the rule that required the marker lamps. At first, the proposed legislation was going to require every *car* to have SML in by Jan '68 which would've been mid-year change. The car makers were already ahead of this and adding the SMLs on cars prior, starting in mid 1967 with car production for the 1968 model year... but (if I recall correctly) the lights weren't going to be required on pickups yet. Then a bit of congress vs bureaucrat back and forth, and the proposed change was amended to lights OR reflectors for the first year (but now including trucks), THEN, 12-31-1969, lights would be required for all vehicles.
GM, in a bit of a scramble to add the trucks to the program (and still be well ahead of its implementation date), went the reflector route on trucks until 12-31-68. They had lights on all models of their cars (as far as I know) already in place for all of the 1968 models.

Another oddity is that *big* trucks (over 80" wide) were required to have the full-on lights from 1-1-1968. It actually started from the big trucks, first, then down to pass cars.

This shot below is from a report fifteen years later, evaluating the effectiveness of the rule (it was very effective)

Re: Side marker "lenses", what's the deal?
 

If you don't want to buy new ones, look on the parts board here as there is always selling decent used markers for 30/40 bucks a set of 4. If you don't see any for sale put a Wanted To Buy WTB post on the parts board. You would have to pay and be a subscribing member to post in the For sale Section.

Re: Side marker "lenses", what's the deal?
 

Yes, the front and back reflectors were the same type, just amber in the front and red in the back. So it looks like mine was made just before the lighting requirement.

Besides the reflector itself not having the bulb holder, my wiring harness does not put wires for adding a bulb near that hole on any of the 4 corners of the truck. I am not clear what sort of lighting goes there, if it is supposed to be just running lights or turn signal too.

Re: Side marker "lenses", what's the deal?
 

Yes, probably. New lenses will be about $100. A little more if I get the lenses for the front turn signal, and rear back-up lights, which don't have reflectors and are not technically needing replacement, but I probably will. I am over budget right now, and concerned.

Re: Side marker "lenses", what's the deal?
 

Thanks, that is good info. If I go ahead and get the new lenses with holder and they have the cross shaped hole, where do I get the bulb holder? Is there a name for those? If I'm going to replace these reflectors I might as well just go ahead and light them up.

Re: Side marker "lenses", what's the deal?
 

Just running lights. Easily spliced in if you had a mind to.

Re: Side marker "lenses", what's the deal?
 

Thanks, that is great info.

Thanks. Not very easy to splice if I can't figure out a bulb holder that fits the lens assembly to splice in.

Re: Side marker "lenses", what's the deal?
 

There was a lot of confusion over what the final requirement would have in it and each mfr had to decide how to address it.
Chrysler took this approach

Re: Side marker "lenses", what's the deal?
 

Do you have any pictures of your wife harness, and is that an option on the spid? :lol:

Re: Side marker "lenses", what's the deal?
 

Your truck would not have the wiring provisions. When I restored my '69 a couple years ago, I stripped the needed front and rear wiring from trucks in a local junkyard. The rears were easy since all you'd need is the rear harness. I found through this process that the wiring varied a bit depending on the year. As an example, the earlier trucks lit all four markers, but the fronts did not flash with the turn signals. Later (year?), the fronts flashed. I think I got 2 different rear harnesses as well, but the functionality was the same.


The bulb holders had the wires molded in. I installed deluxe markers sometime in the 80s and used holders with wires clipped off to fill the holes (as seen in my earlier post). If you can find a junkyard near you that has a couple of these trucks or vans from the from the 70s, 80s and, 90s you'll find lots of bulb holders and markers that will work. The vans up to about 1985 used the same standard and deluxe markers as our trucks. The later years used smoother markers as seen in the picture below.

Re: Side marker "lenses", what's the deal?
 

Wife harness .... You know. Them hooks that go in the door frame with the heavy duty ropes.... Haha. Dang typos

Re: Side marker "lenses", what's the deal?
 

My whole wire harness is near perfect,I can see there wasn't anything for fronts, about afoot behind the cab it gets rough and I couldn't tell on the rear, thanks for the info. I have some old square body harness, I was planning to splice fronts on, I'll have to do the rear when I get there

Re: Side marker "lenses", what's the deal?
 

back in the day when the lenses were unavailable or too expensive, we glued them together with model glue and sprayed them with a spray can clear coat. also spray can painted the part that mounts the bulb with chrome bumper paint. much brighter than nothing or even the white paint often used.

Re: Side marker "lenses", what's the deal?
 

Does anyone know when the turn signals were implemented on the front side markers? The lights on my 70 (built 10/69) did not flash. I installed a front harness that came with my 72 cab and now the front side markers flash with the turn signals.

Re: Side marker "lenses", what's the deal?
 

Do the side markers flash with the turn signals and glow steady when your lights are on and you're not turning? Or are they only turn signals now and have no other light function? Do they behave differently when your headlights are off vs. on? I am trying to picture what could be done to just the wiring to make them have more than one function without a relay or something, and I can't think of a way.

Thank you folks for all the great info in this thread. I went ahead and updated my side markers and all the other lenses on my truck. I found the bulb sockets at O'Reilly Auto, so I'm going to light them up.

Re: Side marker "lenses", what's the deal?
 

First post btw. Just got my 72 C10 Saturday.

It's really easy to make side markers blink even if they aren't supposed to as long as they aren't LED bulbs. Just tap into the turn signal positive wire use that to replace the negative wire of the side marker. If the headlights are on and the turn signals are off that wire will be grounded so the side markers work. When the headlights are on and the turn signal comes on you will get positive voltage on both sides of the bulb so it will go dark. When the headlights are off the positive voltage from the turn signal will go to the normally negative side of the side markers and light them up.

Re: Side marker "lenses", what's the deal?
 

Register your your truck as an antique and put antique tags on it and never have to get it inspected again.

Problem solved!

Re: Side marker "lenses", what's the deal?
 

That is interesting, welcome to the forum, and congratulations on the new truck.

I just finished connecting my new side markers in the back of the truck, and they are now working. I still need to connect the front markers. I will do some experimenting with connecting as you mention, and see if they will behave like that on my 1969 truck.

I have bad headlight switch on the dash and bad turn signal switch in the steering column, so those need to be fixed first, and I have the parts on order. Almost every circuit I run across in this truck is broken, so I'm glad stuff for the truck is relatively cheap to buy. I am kind of amazed when I go to the auto parts store for stuff like fuel pumps, water pumps, brake cylinders, and other fairly major parts like that, and the guy at the register says something like "that'll be $19." It's funny the parts are dozens or hundreds of dollars for my newer cars.

It is time consuming to get it inspection ready. I guess I should have ordered the whole caboodle of switches, bulbs, relays and horns for my truck. I'm hoping the 8-track player works when I get around to testing that. My truck is pretty decrepit, but I sure like it. I hope you enjoy yours.

Re: Side marker "lenses", what's the deal?
 

I am fixing mine up to be a daily driver, so the registration will be classic or regular, and inspection will be required.

Re: Side marker "lenses", what's the deal?
 

OK dudehitt, that is great info. Actually, I love it. I would imagine if you had non-polarity LED bulbs it would work, too. I have seen non-polarity 194 LED bulbs online, but I am sticking with plain incandescent 194 light bulbs for mine, so that is what I tested. Here is what I came up with based on your explanation, I am using the combo scheme in this video:

https://youtu.be/BZ6gb4F1ByA

Re: Side marker "lenses", what's the deal?
 

:metal::metal::metal::metal::metal:

Perfect! I did it on my scion xB. The fronts worked exactly like that. The rears have a sealed led sidemarker unit so they will only blink if the headlights are on.

Re: Side marker "lenses", what's the deal?
 

To finish it off, I soldered together some pigtail T-adapters, so I can just plug into the factory wiring harness at the front turn signal connectors.

Re: Side marker "lenses", what's the deal?
 

Bringing this back up as I will be doing this tomorrow! Ha, I'm getting gold, ehr old I should say.