Will Two Different Garmins, Using The Same Maps And Settings, Use The Same Route?

It may be helpful to understand that it is impossible for the software to compare all possible routes, and thus to give the truly minimum time, distance, ... It makes a good try.

So if the software on different units is not identical, no surprise if the choices are sometimes different.

...I have also noticed that I will get the same results using the same unit. For instance, if I am taking a long trip I will run the route prior to leaving. If I run the same route, say, two months later, it will sometimes send me a different way. Maybe this is due to road improvements or changing of speed limits, I don't know, but it occasionally happens. I have also noticed this happening when I drive to my in-laws. Sometimes it will send me one way and another day, a different way. Again, traffic? I don't know. Can't figure it out.

I have two 3597's as does my brother. We often have both our 3597's booted for various reasons when travelling together in separate vehicles. We have noted that each of the four units will select different routes to the same destination!

As an experiment, we carefully set all options identically and loaded the latest firmware and map update in each unit. We have not yet been able to get all four units to agree on the same route!

These experiments were done in rural areas with many possible routes which are greater than 25 miles. There are also no obvious roads involved like interstate highways.

When we get together next, we'll try doing a master reset on each unit which should eliminate the possibility of "My Trends" affecting the routing. I've heard My Trends is supposed to reset after a map update but I've not been able to verify this.

I've found that my 350 and 2598 will at times route differently when the same destinations are input into each device. Sometimes its a head scratcher how the older 350 routes compared to the newer 2598.

Several years ago a friend and I were attending a state RV rally out of town and we both decided to take a couple of carloads of friends to the same restaurant about 5 miles across town (no highways involved). We were parked beside each other when we entered the location on our different nüvi models of similar vintage with the same map sets installed. Our fastest/shortest choices, etc. were identical. We arrived within a minute of each other following completely different routes. At that time, we didn't have traffic devices either. We both had technical backgrounds and our conclusion was that they were simply different under the hood. So yes, some of us have had a chance to observe the same thing.

Garmins can change their minds too, be moody, argumentative, just be careful they do not get mad at you.

myTrends is a wild card in this scenario and your conclusion to perform a hard reset and then verify that myTrends (as well as trafficTrends) is disabled before testing again may be a good bet that you will get the same routes.

myTrends is found under Settings > Device. trafficTrends is found under Settings > Traffic.

I also have one Garmin Nuvi 3597. When I drive around, I usually have it navigating, even when I don't need it. Last weekend, I drove to my local MicroCenter. On the way back, I had it routing what it determined to be the fastest route. Ironically, I turned off the route it had selected a few miles in. Interestingly enough, it showed that the route I took was faster!

I also have the most current firmware on the 3597. So, I guess it just goes to show you that even if you have selected either the shortest or fastest route, it might not necessarily be either one!

Have noticed for years each will do a little different on the routing.

I have found that when going on a local errand, my old NUVI 750 can pick one route for going and a different route for returning. I also thought it rather odd because the old 750 model doesn't have traffic nor any of the newer model features.

...of a time a number of years ago when I was using my 350. I was down in Virginia heading back home when I had to take a detour. I was following the detour until I made a turn that I knew would get me to where I wanted to go faster. Lola, (gps's nickname) came out with the dreaded "re-calculating" and suggested the same route I had been traveling. When I refused to make another turn as suggested, Lola again, did the dreaded "recalulating", but in a somewhat more severe tone. My wife and I thought this was funny and continued on our path towards civilization. Another missed turn and Lola became really angry. At this point we were having a great time laughing at Lola and 'her' attitude. After the next missed turn, my gps shut down. At this point I figured I had gone a little to far and I was in the literal "Lola" dog-house. I have never had that happen since. Was "Lola' really ticked off or was it an electronics overload? I guess I'll never know.