GPS Speedometer

[85_Ranger4x4]

Has anyone on here used one?

Do they really need the antenna outside the vehicle? (preferably on the roof)

I really don't want the antenna on the roof... and if I have to have one I think my slide in camper will block it anyway. I really don't want it on the dash either...

I had a thought last night, my Garmin GPS doesn't need an antenna to read the vehicle speed, and even with the handheld under the dash on the transmission hump (for testing) still reads the trucks speed accurately.

 

[Curious Hound]

I've been wondering the same things. My phone and tablet seem to do fine inside the cab.

I think it may be a case of deciding what you believe is "acceptable error. On a big flat roof with unobscured line of sight to the sky, logically seems best. But if it is "accurate enough" when sitting on the center console inside or on the transmission hump, then, why bother with a fancier mounting location?

I'm going to have the OEM VSS signal going to my digital dash. So I have a good speed signal. But I will probably connect the gps antenna and display that speed also, for comparison. I'm considering mounting the antenna on a small steel plate on the dash, or directly on the flat strip of cowling right in front of the windshield outside. The nice thing is that with magnetic mounting, it is relatively easy to experiment with different locations.

 

[Ranger850]

I got one of these. It plugs into a USB and projects on the windshield HUD style. I use it in my Nissan because the speedo needle has fallen off too many times to count. It's dead on accurate with my phones GPS, as far as MPH goes. It's real simple to use. Plug it in and go. It does take longer to "connect" sometimes, but we're talking 10 seconds, not minutes or anything.

Smart In-Car HUD Co-Pilot GPS Speedometer, Heads Up Display with Large MPH Digits - Walmart.com

Buy Smart In-Car HUD Co-Pilot GPS Speedometer, Heads Up Display with Large MPH Digits at Walmart.com

www.google.com

 

[JoshT]

I have something similar to Ranger850 in the F-100 because I can't trust the speedometer in it to work consistently. It sits on the dash, no external antenna, and it has been accurate with everything I have checked it against. Other vehicles, standalone GPS, phone, and those roadside speed camera signs.

Convinced enough that when I eventually install a Dakota digital dash, it'll use GPS for speed. Same for anything I put aftermarket gauges in.

 

[4x4junkie]

I've noticed maybe about 5-10% of the time the GPS on my dashcam will fail to pick up any GPS signal for like 10 minutes or longer, occasionally not even before getting to my destination over a half-hour later (cam is mounted on windshield behind mirror).
Not sure if this is the cam itself, something with the GPS signals, or if a dedicated GPS speedo would have the same issue, but in such a case a GPS speedo would also read completely blank (I think I'd rather have a hard-wired / hard-cabled speedo myself, at least to fall back on).

 

[85_Ranger4x4]

I've noticed maybe about 5-10% of the time the GPS on my dashcam will fail to pick up any GPS signal for like 10 minutes or longer, occasionally not even before getting to my destination over a half-hour later (cam is mounted on windshield behind mirror).
Not sure if this is the cam itself, something with the GPS signals, or if a dedicated GPS speedo would have the same issue, but in such a case a GPS speedo would also read completely blank (I think I'd rather have a hard-wired / hard-cabled speedo myself, at least to fall back on).

Currently I am mainly using the GPS speedometer on my Garmin lol.

Stock speedometer can not be geared 100% correct for my tire size (reads 4mph low at 60mph) and has a bounce to it. I have a thread on the rest of my 40 year old gauge woes HERE

I am just researching options that won't effect the VSS in the t-case that also drives my cruise control.

I also have a VSS in my Explorer axle but info is limited on how well that works for aftermarket speedometers. Most hotrods getting aftermarket speedometers don't have VSS's in the axle...

 

[Curious Hound]

I just did a google search on this. If we can trust the AI results, see the screenshots below. It seems the main thing is to make sure metal (like the roof) is not blocking the signal. The ideas of mounting the antenna inside the dash are interesting. Although you would still want it as far forward as possible so the roof doesn't interfere. But, plastic and untinted windshield glass are ok.

 

[85_Ranger4x4]

I just did a google search on this. If we can trust the AI results, see the screenshots below. It seems the main thing is to make sure metal (like the roof) is not blocking the signal. The ideas of mounting the antenna inside the dash are interesting. Although you would still want it as far forward as possible so the roof doesn't interfere. But, plastic and untinted windshield glass are ok.

And then the metal first gen dash enters the chat...

 

[Curious Hound]

Currently I am mainly using the GPS speedometer on my Garmin lol.

Stock speedometer can not be geared 100% correct for my tire size (reads 4mph low at 60mph) and has a bounce to it. I have a thread on the rest of my 40 year old gauge woes HERE

I am just researching options that won't effect the VSS in the t-case that also drives my cruise control.

I also have a VSS in my Explorer axle but info is limited on how well that works for aftermarket speedometers. Most hotrods getting aftermarket speedometers don't have VSS's in the axle...

I would think the vss in the axle should work fine as long as the speedometer device you choose allows you to program the correct # pulses per revolution or pulses per mile.

 

[Curious Hound]

And then the metal first gen dash enters the chat...

Ok. Didn't realize you had a metal dash. I wish I had a nice, durable metal dash.

 

[85_Ranger4x4]

Ok. Didn't realize you had a metal dash. I wish I had a nice, durable metal dash.

It would be.

The plastic cap they put on the edge right in front still cracks and falls apart lol. The panel across the top the speakers mount to is steel also.