Why one route out but a different route back ?

 

Recently used my Nuvi 1490LMT to successfully guide me to a destination I've never visited before. Performed flawlessly ! Return trip was another story...unit did not "retrace" route out but instead routed me back using a completely different route. Anyone else have this experience ? Why wouldn't same route be used in reverse ?

Right turns vs left turns

Often the unit routes differently based on using right turns as opposed to left turns. Left turns are "more dangerous" or "more difficult" or something of that sort.

I visit an office in Fair Oaks (Northeast Sacramento area) and my nüvi always routes me there one way and back home another way.

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GPSMAP 76CSx - nüvi 760 - nüvi 200 - GPSMAP 78S

Reverse route.

The route can also be affected by one way streets, medians restricting turns, interchange/junction topology. On the newer units with Traffic Trends, if you have that feature enabled, the time of day/day of week can affect the route.

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Alan - Android Auto, DriveLuxe 50LMTHD, Nuvi 3597LMTHD, Oregon 550T, Nuvi 855, Nuvi 755T, Lowrance Endura Sierra, Bosch Nyon

Not unusual

I have a TomTom, not a Garmin, and it has occasionally done the same thing. Upon investigation, I found that it uses a different timing for left turns than for right turns, especially on multi-lane roads. I assume that this is on the assumption that there may be a need to wait for a little while for either a left turn light or for a safe opportunity to make a left turn across traffic.

If there are a number of turns on the route, this could end up with a visibly longer travel time in one direction than the opposite direction if taking the same route. This might make it quicker to take different routs depending upon the direction of travel.

With best wishes,
- Tom -

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XXL540, GO LIVE 1535, GO 620

To throw off your tail if your being followed

Never use same route and create a pattern, lol

Return Route Always Different

Every Garmin I've owned since 2008 has worked that way. If you go from A to B and Back, it won't follow the same route.

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DriveAssist 50 (stolen), Nüvi 2595LMT

Avoidances

cruisefor2 wrote:

Why wouldn't same route be used in reverse ?

Digging up the classic possibility of having chosen to avoid Toll Roads, I've been on bridges that only have tolls in one direction.

Right Turns

My nuvi seems to prefer right turns.

Donuts

Because you stopped at the Donut shop on the way there, and it knows you're supposed to cut down on those.

Toll Bridge.

bwarden wrote:

Digging up the classic possibility of having chosen to avoid Toll Roads, I've been on bridges that only have tolls in one direction.

I never thought of that. But my 1450 thinks that the Mississippi bridge is toll both directions. It is not however. It costs me a buck to leave Ft. Madison IA. It cost nothing to go there from Illinois.

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1490LMT 1450LMT 295w

UPS drivers like right turn as well

beagle.fan wrote:

My nuvi seems to prefer right turns.

Unless absolutely necessary, UPS drivers also prefer making right turns.

Few reasons have been discussed: right turn is safer than left turn, less CO emission (because less waiting on idle for red lights and incoming cars), etc.