Gas tank size? I think my gauge is lying to me

[Romulus]

2005 Tahoe Z71 here.. all sources I see say that we have 26gal tanks. Since I've owned the truck (2 years), when the gauge hits E, I can put 18-19gallons in the tank. Does it really have another ~7 left? I've been debating throwing a 5gal jug in the back and seeing how far the truck will go, but figured I'd ask here first.

Also, if the gauge indicates E and slowly rises after the truck runs for a few minutes (on a full tank), does this mean the fuel sending unit is going out?

 

[mizzouguy]

My 04 also has a 26 gal tank. If i go to empty, as in the light comes on and I fill it, it'll only take 20-21. I've gone way past empty, DTE went from 30 to low, then I drove another 50 miles or so and still only took 24 at fill up. Never ran out of gas at that point either. I'm pretty convinced it actually holds 26 and the gauge will show empty with roughly 5 gallons left.

When I fill mine and hop in and start it, gauge slowly rises to about 7/8 full and then it'll creep up to full by the time I get home. Probably sending unit getting old and build up. Ran several bottles of techron and no change.

 

[01ssreda4]

They swear denalis have 29 gallons or whatever but mine takes about 20 to fill and when i went over E it DID run out of gas about 45 miles later.

 

[ccapehartusarmyINF.(ret)]

my tahoe even after driving it 30 or 40 miles with the gas light on it would only take 24 almost 25 gallons
now i did run it dry before and it took almost 26gallons to fill it now i did notice also that when it was bone dry a gallon wouldnt even start it it took almost 2 gallons before itd start

 

[ccapehartusarmyINF.(ret)]

now my suburban takes 32 gallons and when ive filled it up with the needle well below e it takes 32 gallons to fill it

 

[YukonXL04]

now my suburban takes 32 gallons and when ive filled it up with the needle well below e it takes 32 gallons to fill it

This is exactly how my yukon is. 33 gallon tank. Put 30-31 in on occasion. My wife loves that low fuel light...

 

[ccapehartusarmyINF.(ret)]

1500 comes with a 32 gallon the 2500 comes with a 38 gallon

 

[Chizzychase]

Most I have ever put in my truck was 21-22 gallons.

I figured it was the same size as the silverados and sierras but I could be wrong. Fuel related things on this body style tahoe/yukon are wonky if you ask me!

 

[ccapehartusarmyINF.(ret)]

trucks all have a couple different fuel tank sizes depending on if its extended cab crew cab short bed or long
tahoes done have as much room to work underneath as trucks

 

[retiredsparky]

It is not wise to run the tank empty. The fuel pump for most gasoline vehicles including Tahoes can overheat if there is no fuel left in the tank. The fuel surrounds the pump and absorbs the heat.