GM 4905/4108 Convex Mirror

richard5933 · August 26, 2019, 04:46:29 AM

On the cover of the service manual for the buffalo buses there is a photo of the bus. If you look at the photo, you see a convex mirror mounted halfway up the A pillar on the passenger side of the windshield.

I don't see any sign of a mounting point on my bus's A pillar, and I can't find any mention of this mirror is the parts manual.

Anyone know anything about these mirrors?

Perhaps they were something that never made it into the production models?

chessie4905 · August 26, 2019, 05:14:58 AM

Both my mirrors have an angled metal bracket at the top to hold convex mirrors.

richard5933 · August 26, 2019, 05:45:11 AM

Quote from: chessie4905 on August 26, 2019, 05:14:58 AM
Both my mirrors have an angled metal bracket at the top to hold convex mirrors.

Yeah - I've seen that setup on a number of buses. What I'm trying to figure out is if the photo on the cover of the service manual is something that ever made it to production buses or not. The only place I've seen the mirror is on the photo on the cover of the service manual - it's not in the parts book anywhere I can find.

chessie4905 · August 26, 2019, 12:47:36 PM

If I recall, you said you have the older style mirrors with the metal heads. My parts coach has one of these and the other one is the new style with the plastic housing. Here is a picture of the one like yours with a bracket for a convex mirror. The mirror is gone, but it was a 6" convex with a threaded stub.

buswarrior · August 26, 2019, 02:53:08 PM

Post up a pic of this manual cover please?

Happy coaching!
Buswarrior

richard5933 · August 26, 2019, 03:33:38 PM

I think that the cover of the manual is the only place I have seen this.

chessie4905 · August 26, 2019, 06:06:50 PM

That looks more to see the entrance door for entering or departing passengers. Do a search for 4107-4905 images to see how common it was.

richard5933 · August 26, 2019, 06:32:37 PM

I was only able to find one photo online so far with the mirror - it looks like it sticks out almost as far as the regular mirror.

Has anyone ever seen one close up? Was this a factory option or something aftermarket? Curious why it's on the cover of the service manual but not in the parts book.

chessie4905 · August 27, 2019, 03:53:58 AM

Probably an early option with almost no takers. Happens all the time. Remember rear wheel steer GM pickups, and Pontiac 6000, GMC Encores with sliding roofs, Ford retractable hard tops, 45 rpm under dash players, etc.

lostagain · August 27, 2019, 06:38:28 AM

A convex aimed at the side of the door would be helpful to see if there is a small car or a bicycle or motorcycle beside you. The regular convex, if pointed a little high, does not show that area. That is why some trucks have the mirrors mounted on the front corners of the hood. I find them really helpful. Some buses, and trucks, have a window in the lower part of the door for that same purpose. Some of the new Prevost cars have a convex up in the upper left corner above the driver (inside), that you aim so you can look out the door window and the first window to see traffic there. I never used it much because it is so high, you have to twist your neck up to look at it.

JC

DoubleEagle · August 27, 2019, 09:22:48 AM

The most useful mirror on many trucks I have driven was the large convex mounted on a tripod stand on the front fender. It was good enough to check the entire right side and spot the trailer wheels going around corners. Having an equivalent on a bus is a little difficult, but then there is less length to cover. The Ramco Engineering mirrors with the built-in convex, or the add-on convex, seem to be the best for buses.