This is a good question and not discussed in RV circles. The answer is that, like TT disc brakes, the industry and public has no real idea of what a difference good mirrors make.
The DODGE towing mirrors are no better than those from GM or FORD. Adequate, but not very informative.
The test for the main mirror is
the point of convergence [POC] Measure it. Adding
ORA, or similar reduces this problem.
The convex section of OEM mirrors is almost nothing more than cosmetic. One needs a convex spot of 5" or larger to make fast lane changes possible. (We use 9" on big trucks, where, remember, the TTL length is at 72', and RV rigs like mine are at the RV maximum of 65'. My big truck/trailer combo is usually shorter than my RV).
Having to change eye focus is the giveaway: too small means being of no use when it matters.
FORD and GM both have mirrors seen on box vans with a long arm and a big head with almost-decent convex.
I've changed my DODGE tow mirrors to one with a larger head for the main and will be adding a large spot at some point (DIY fab). Maybe extensions as well.
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Linear Mode
