Gas Tank Issues, pump, picckup, sending unit???? HELP

[rms25thta]

Hey guys, hopefully someone can help me clarify what is going on. I have had my Tahoe for two years now, 02, 5.3 Flex Fuel version. When I bought it, the prior owner informed me that when the tank gets down to 1/4 that it will run out of gas. He said that he had the fuel pump replaced and that the pickup was in the wrong position. Well, at 1/4 tank he was right, it would be out of fuel. I have changed over to Escalade gauges and it seems that the 1/4 level is a little different with these gauges and now the safe "refuel now" level is between 1/4 and 1/2 tank. After to talking to a mechanic, he said that it sounds like it has the wrong pump in it. He said that the 26 gallon pump is different from the pumps that go in the bigger tanks that are available in the Suburban and Yukon XL's. I have not dropped the tank yet but wanted to get some feedback from you on what you think of that theory. If you can shed some light on it I would greatly appreciate it. A few weeks ago I ran out of gas when the gauge was at about 3/8......I was running 75 mph on I-95 north in the fast last and the truck shut off, pretty scary with the family in the vehicle. Please help if you can.

Rich

 

[M3PO]

It makes sense, that if the pickup is not down far enough(either installed int the wrong position or wrong assembly), it wont pump fuel. I know hind sight is 20/20, but adding another variable (different gauges) is never a good idea until you get the first problem fixed; there is no rule saying you can't have two related problems at the same time.
When you ran out of gas, did you fill it ALL the way up and pay attention to how many gallons it took to fill and then compare that to what the actual capacity is? If your pickup is not at the bottom of the tank, the motor will die before the tank is actually empty.

 

[rms25thta]

Yes. when I ran out, I put 2 gallons in on the side of the road, drove to the next exit, less than a mile and put 16 gallons in to fill up, so 18 gallons total to fill the tank. Simple math says I still had 8 gallons of fuel in the tank seeing that I have a 26 gallon tank.

If it does have the assembly for the larger tank, which I am told has a shorter over all length, is there something I can do to fix it without replacing the whole thing??

---------- Post added at 01:25 PM ---------- Previous post was at 11:53 AM ----------

Just wondering, how many miles are you guys with 26 gallon tanks getting out of a full tank of gas??

 

[M3PO]

If it is the wrong pump, you are probably going to have to replace with the right pump.
If you have a 26 gallon tank and most of these trucks get roughly 15MPG= 390.
I don't get near that many miles, but when I hit the fuel light the other day, I put 20 gallons in so maybe my Denali has a smaller tank, or the fuel light comes on with 6 gallons to go. Either way, that is the second time I saw the fuel light, I normally don't go bellow 1/4 tank.

 

[ntxstallion]

I think the fuel light is sent by same things that tells you the mpg on the DIC. When my fuel lights comes on I spend about 75 per fill up. This is with gas around 3.55 to 3.68 per gallon(87 octane). I did not remember the miles cause I wasn't looking. I am due for a fill up soon(73 miles to empty). I think that the empty light at 5-6 gallons is correct. Given the amount I have left to go and doing the math.

 

[ntxstallion]

Just filled up from 69 miles to empty and it took 20.20 gallons to fill it up at 3.68 a gallon.