# 18 gal tank doesn't hold 18 gal

**URL:** <https://community.cartalk.com/t/18-gal-tank-doesnt-hold-18-gal/6789>\
**Category:** Maintenance/Repairs\
**Created:** [November 3, 2007, 8:05pm UTC](https://community.cartalk.com/t/18-gal-tank-doesnt-hold-18-gal/6789 "2007-11-03T20:05:38Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![femaletamale](https://avatars.discourse-cdn.com/v4/letter/f/c68b51/32.png) [@femaletamale](https://community.cartalk.com/u/femaletamale)\
**Post date:** [November 3, 2007, 8:05pm UTC](https://community.cartalk.com/t/18-gal-tank-doesnt-hold-18-gal/6789/1 "2007-11-03T20:05:38Z")

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My older Maxima fuel tank is supposedly 18 gal capacity. I have not let it get lower than 1/4 tank remaining, but 9 gal will fill it up when it is at that point on the fuel gauge. I don’t get it. What’s up with that?

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**Author:** ![SteveF](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/stevef/32/2_2.png) [@SteveF](https://community.cartalk.com/u/SteveF)\
**Post date:** [November 3, 2007, 8:54pm UTC](https://community.cartalk.com/t/18-gal-tank-doesnt-hold-18-gal/6789/2 "2007-11-03T20:54:25Z")

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The simplest explanation is that when your gauge shows 1/4 tank remaining, you still have half a tank of gas. I wouldn’t be surprised if you could drive another 200 miles with that ‘quarter’ tank.

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**Author:** ![Naruto\_1](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/naruto_1/32/429_2.png) [@Naruto\_1](https://community.cartalk.com/u/Naruto_1)\
**Post date:** [November 3, 2007, 10:26pm UTC](https://community.cartalk.com/t/18-gal-tank-doesnt-hold-18-gal/6789/3 "2007-11-03T22:26:54Z")

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it can be a dented fuel tank or a fuel guage sender problem or the guage is broken

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**Author:** ![Joseph\_E\_Meehan](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/joseph_e_meehan/32/21_2.png) [@Joseph\_E\_Meehan](https://community.cartalk.com/u/Joseph_E_Meehan)\
**Post date:** [November 3, 2007, 11:24pm UTC](https://community.cartalk.com/t/18-gal-tank-doesnt-hold-18-gal/6789/4 "2007-11-03T23:24:09Z")

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Few fuel gauges are anywhere close to accurate. They generally will show full if the tank is full and will show empty when the tank is empty, but anything else is anyone’s guess. Some are close, but many are way off.