GPS Accuracy

After I updated to 5.40, my EPO showed expired. Syncing didn't fix it. It showed Current the following morning. Not the first time I've seen this after an update, and one more reason I'd be hesitant to update immediately before a run. The F5 doesn't delete the epo.bin file after reading it after a computer sync, unlike the F3, so I could check it had an up to date file.

5.40 hasn't actually changed the GPS firmware, as others have said.

Why isn't this post sticky like the ANT+ connectivity issues post?

I wouldn't expect any big improvement to GPS tracks, however Garmin may continue to improve distance tracking by other means. This means using accelerometer, gyroscope and footpod (when connected) to patch up the mediocre GPS performance. These are already used in the ultratrac mode as well.

As such I've found the distance calculation from my F5 is actually pretty good. Only instant pace leaves room for improvement lacking under heavy wood cover for example.

I wouldn't expect any big improvement to GPS tracks, however Garmin may continue to improve distance tracking by other means. This means using accelerometer, gyroscope and footpod (when connected) to patch up the mediocre GPS performance. These are already used in the ultratrac mode as well.

As such I've found the distance calculation from my F5 is actually pretty good. Only instant pace leaves room for improvement lacking under heavy wood cover for example.

What do you mean by: "As such I've found the distance from my F5 is actually preety good"?
Indeed that's the problem I have with my fenix 5. The distances are quiet systematically under-estimated (by 3-4%) even with "clear sky". As you said, I hope that by using better the accelerometer and the gyroscope they will improve the recorded distances. I really need to have a good average pace for each of my laps. It's more important that having good GPS tracks.
The problem is that I'm not sure Garmin is aware of the problem...

What do you mean by: "As such I've found the distance from my F5 is actually preety good"?
Indeed that's the problem I have with my fenix 5. The distances are quiet systematically under-estimated (by 3-4%) even with "clear sky". As you said, I hope that by using better the accelerometer and the gyroscope they will improve the recorded distances. I really need to have a good average pace for each of my laps. It's more important that having good GPS tracks.
The problem is that I'm not sure Garmin is aware of the problem...

I mean even on one run where my distance was 4% off (clearly bad GPS track) the watch recorded distance was still only 1% off. Usually I get well under 1% error which is good enough for my training.

Still I wouldn't say my GPS tracks are very pretty. They mostly follow the road but are offset at times. At slower speeds (recovery breaks) even quite jumpy. Still for custom interval training for example my laps fire at exact same spots and total distance is accurate. This is a clear indicator Garmin don't use just the raw GPS track which may change from run to run but also have other means to keep the distance data in check.

If you get 3-4% off systematically and even under clear sky then I'm afraid there must be something wrong with your watch.

EDIT: I noticed from your earlier post you've already changed the watch and the tracks aren't actually that bad. Do you have a foot pod connected and is it calibrated properly? I've noticed a foot pod with wrong calibration factor may throw distance off even when used for pace only. Another thing to check is to see if you're doing any out of ordinary movement pattern with your hand as this might affect the wrist dead reckoning algorithms. Other than that I'm out of ideas...

I love my Fenix 5 but the accuracy in the woods is very iffy. On my trail run last night I used my iPhone 6 and Endomondo as backup. The Fenix 5 track was 5.8 miles which was consistently shorter than the trail markers while my iPhone logged 6.89 miles. I can live with a little difference but over a mile variation in a 6-7 mile run is awful. Any suggestions.

I attached a link to a comparison of the files.

http://www.mygpsfiles.com/app/#liamO6Yp

I had both GPS & Glonass turned on, I ran 6.5 miles, it gave me about 8.5 miles. It calculated one mile at 1.5 min/mile pace. The map shows I ran into the ocean... into buildings and even squibbly routes... Very weird and disappointed. When it uploaded to Strava, their team mentioned there's tons of error in the uploaded data. This happened many times but seems to happen certain part of the city and time of the day. Same routes with my older 735xt didnt have that issue. Can someone help?

I had both GPS & Glonass turned on, I ran 6.5 miles, it gave me about 8.5 miles. It calculated one mile at 1.5 min/mile pace. The map shows I ran into the ocean... into buildings and even squibbly routes...

I'm having the same issues with my Fenix 5. I'm extremely disappointed. I ran the Sydney half marathon just over a week ago and my Fenix 5 had me running through water, through buildings etc.It added on an extra kilometre too. It was a lovely sunny day, no cloud, not too many obstructions. Looking at others who ran with me on Strava, TomTom's and older Garmin's seem to be the most accurate. Again, looking at Strava, there was a lady running with me with a Fenix 5S and someone else with a 5X. Both were like me, running through water, buildings etc. and with at least an extra km in distance!

I have noticed that when I run through or past obstructions, that seems to be when it starts going downhill. It's like it never recovers.

I have been running with per second recording enabled, and with GPS+Glonass.

Yesterday just after my Fenix 5 upgraded to the lastest software (v6.0) I tried a run with both my Fenix 5 and Samsung Galaxy S7 Edge with Strava recording. Over 12 km, the phone with Strava was spot on, it even coped when I ran past a building site with scaffolding. The Fenix 5 lost the plot around the building site and added an extra 0.7 km to the run in total.

I purchased mine directly through Garmin Australia so I'm going to contact them in the next day or so.

Seeing all the various forum posts and comments, I'm going to see if I can return the Fenix 5, although if they DO agree to this I haven't yet decided what I would try instead.

I apologise in advance for using the F word, but my old Fitbit Surge was more accurate! :)

I have read and heard reports where GLONASS actually makes things worse so it might be worth to try actually disabling it...

I now always run with GPS only (though I have a 935 after returning the F5 because of these gps issues) and see no need to enable GLONASS.

Same here! At least it was my conclusion after disabling it. Tracking got way much better with GPS only then with GPS+Glonass.
This was back in the 4.xx days, but I'm using F5 since and I'm finding GPS tracking as good as any other device I've used.

For more info, see this post