Does the C8 really have it, and did everyone else know about it but me? While rummaging through the 7000 page 2020 Corvette Service Manual, I ran across this description for Automatic Headlamp Leveling. I included the description and schematic. Sorry if its old news - I did search the forum for that term and did not find anything.

 

If old news....it's new news to me! Thanks for the post.

 

I hear it's an option for the 2023 MY.

 

Where?

 

I wondered about it too when the corvette blogger website mentioned it as if it was a new feature for 2023 - the TR7 RPO code: https://www.corvetteblogger.com/2022...-order-system/

As others on this forum have noted, GM sometimes mentions features in manuals that a model doesn't have. For example, the 2021 and 2022 C8 owners manual mentions AEB and ACC as if the C8 has them..

We usually don't buy vehicles without manual or automatic headlight leveling but I didn't think it mattered much for the C8 since it has front and rear trunks and is less likely to sag in the back to the extent that the headlights don't light up the road. We were about to to get a plug-in hybrid RAV4 for my wife last year until we discovered that headlight leveling wasn't available on it.

It could be difficult to tell if a C8 has automatic headlight leveling. Some automatic headlight leveling systems, like on a Lexus LS with HID headlights we had, do a very noticeable up and down "dance" each time the engine is started. The automatic headlight leveling on my wife's current 2012 Prius v wagon with LED headlights doesn't do anything noticeable on start-up. Our Toyota Sienna van has a rotary switch on the dashboard for the headlight level. When a driver on the opposite side of an intersection won't dim his headlights while we're stopped at a traffic light, I've found that manually moving the HID beam upward and burning the other driver's eyeballs is quite persuasive in getting the other driver to dim his headlights.

 

https://www.corvetteactioncenter.com...-with-options/

Option code TR7

 

I found a little more in the 2020 Service Manual. A list of what is considered the "components" of the leveling systems. If (or when?) it has it, it appears that the actual leveling is inside of what is called the headlamp assembly. The "headlamp leveling front suspension height sensor" appears to be separately replaceable component. I also added the sections from the 2020 Service Manual that is called "Front Suspension Automatic Forward Lighting Position Sensor Replacement". These are added to the OP (or will be momentarily)

 

Thanks. I see it there. Its interesting that while many of the descriptions in the service manual start with "may have" or "if equipped", or some similar caveat - this particular description lacks that caveat.

 

Headlamp leveling is required for certain vehicles in Europe. I suspect that as part of the development to homologate the car for Europe they had to add this and that's why it's on the order guide now, although it'll be interesting to see if it's actually orderable in the US.

 

More cost, more weight, more things to break. No thanks.

 

Just checked the availability of the headlight assembly for 2020. The listing shows its available two ways. Its available for "without ground clearance control / without leveling", and its it available with ground clearance control/with leveling. Is ground clearance control the front lift option?

 

^^^
Strange that it costs more for the ones without leveling. I would have thought it would be the other way around.

But interesting question. I've seen no indications that my 3LT MSRC Z51 with front lift has leveling but I haven't looked for it.

But I could see how it could be a legal requirement to keep oncoming cars from being blinded if I was using the lift.

 

You bought up an excellent point. Automatic downward beam lowering could be important to keep from blinding oncoming drivers when using the front lift.

 

The auto leveling on all the cars i've owned adjust on startup. While driving they don't adjust up or down...

 

No doubt, but the headlight leveling referred to in the Service Manual, as described in the OP, occurs "as the vehicle travels.." It describes a real time adjustment.

 

So someone with Front End Lift needs to start their car in the garage, note the level of the headlight beam with the lift lowered, then raise the front end and see what happens.

If the FEL equipped cars really do have this, it would be relatively easy for GM to put it on cars without FEL as a stand-alone option. But nowhere in GM's printed or online literature have they ever mentioned it (prior to the leaked 2023 order entry form).

 

I tried this on my 2020 3LT MSRC Z51 with front lift. Initially, my answer was going to be "no" since the headlights raised and lowered when I cycled the lift. However, on closer examination, the headlights don't seem to raise and lower proportionally to the lift raising and lowering. And while the lift raises and lowers smoothly there is some jerkiness (like steps) in the headlight beams while the lift is raising and lowering. So my answer is now "perhaps".

 

I've been thinking about that. The height change of the car is only 3 inches or so. If the headlight adjusts to compensate it will be an angular adjustment, so as the car raises, the angle of the lens will adjust down slightly. Because its angular, it can only keep the height of a beam spot the same at one distance. If you do an alignment using a spot on the wall at 25 feet difference, the angular adjustment to keep the spot at the same height when the car raises 3in is 0.57 degree (quite small). The logic in the car may assume a different reference distance to calculate the adjustment - so the angular adjustment may be different. Also, this only accounts for change in height of the beam. The "angle" of the car probably changes as well, since the front raises and the rear does not, so it may adjust for that as well. My point is just that the angular adjustment will be quite small, and will only keep the beam height the same at one reference distance. I did watch the lens while my wife raised and lowered the car, and I think it does tilt downward as the car raises, but the adjustment is very small and you really have to look closely to see it. ( I am talking about the inner lens that looks like a magnifying glass).

 

As the headlights are angled slightly downwards, measuring a couple of feet from the nose of your car will show that the cutoff line goes up even with headlight leveling or compensation for the front lift, even though the center of the beam points at the same point on the road. Conversely, if the lights are non-leveling, the cutoff line should go up slightly more than the nose of the cars, as the angle of the beam center changes upward. The discrepancy would increase with distance of the measuring plane from the headlights.

 

Yep, think of it this way. If you parked your car with its nose about an inch from the wall and raised it, if the low beans were at the same place on the wall then they would be aiming at a point that is a lot closer than when the car is lowered. Low beams are usually aimed to illuminate about 200' ahead so that is the aiming point that needs to be maintained.