Gas tank

[72cut]

Ok guys I just put a new fuel pump in my 88 lab, I eventually want to put a new tank on. Yes, I've read previous posts and I've read about 16, 18 and 23.5 gallon tanks. Different people say different things. I can tell you I felt 2 baffles on bottom of tank and I think it has 3 straps. 

So question is, is there a definitive way to tell by looking at it?

If not and I currently have 16 or 18 gallon and I buy a 23 gallon by mistake will pump still work or vice versa. What do I have?

[Gojira94]

If it has 3 straps and you're a long wheelbase/ long bed, that sounds like the 23. A 23 won't fit on a short box.

 

Sending unit/ pump arrangement is same for all 18 & 23 gallon tanks specific to MJ. XJ sending units are different.

Edited July 24 by Gojira94
clarification

[eaglescout526]

If it’s the original tank, it will have a date and gallon plate by the sending unit opening. Long beds came with 16 or 23. 16 will be identified by a shorter arm on the sending unit and the filler tubes inside will be longer than the 23 gallon. 

[Gojira94]

5 minutes ago, eaglescout526 said:

16 will be identified by a shorter arm on the sending unit

 

I was not aware of this. MTS makes no distinction about the arm on their units made for 18 & 23, so at least those are the same.

[eaglescout526]

8 minutes ago, Gojira94 said:

 

I was not aware of this. MTS makes no distinction about the arm on their units made for 18 & 23, so at least those are the same.

Yeah 18 and 23 are the exact same sending unit.