Miles till empty just increased drastically

Hi,
2011 toyota sequoia platinum 160K miles 5.7 liter. EVERY time I fill up - about 21 gallons, the miles to empty says "285" or something very close to that - maybe 289 or 293.... but last time I filled up, it said "393 miles till empty" - the only recent change was installing a new battery. Anyone know why this might be happening? Is it cause for concern? Thanks!

 

It's because of the battery, when you unplugged the old one the trip computer reset so it's optimistic about your mpg and thus your miles to empty. Once it realizes the truck gets 7mpg it will fix itself.

 

ha! Damn straight! freakin' 9 city, 14 highway.... thanks, that makes 100% sense!

 

Give it a few tanks and it will normalize. Mine was showing 630 miles, I was like, yea right.....

 

Just wondering.. does the 36gal Tundra tank fit in the Sequoia, asking for a friend?

 

I dunno but I found this: https://www.tundras.com/threads/transferflow-larger-fuel-tank.10690/

 

Even just 5 more gallons would be nice.

 

You might wanna check on the fuel pump on said Sequoia, at least for Tundra, 38G tank has a reserve of at least 6G, meaning it is only as good as 30-32G tank limit.

 

I imagine it's the same, from flashing E to full is 21 gallons or so.

 

The miles until empty countdown is a joke. Even after consistent driving, same path, same speed for days on-end, it is nowhere close to reality. It is a random number generator most of the time.

 

The ECU isn't exact too smart, but I have almost 45k miles on my '21 and in regards to combine driving, at least 500 miles, regardless if the empty light comes on or not.
I think one time I got close to 550 miles with light on for a bit, cause I was on my way to the gas station anyway, which was ~25 miles. I did fill 32G in my 38G tank.