[The Hammer]

Does anybody know if the '55-57 pontiac gas tank sending units interchange with the '55-57 chevy gas tank sending units?

If they are, I'd like to avoid paying CPR prices. I've had multiple experiences where they take '55-57 chevy parts and jack the price up 25% and sell them as pontiac parts. Just want to make sure that this isn't one of them.

[frankie m]

I have a 57 Pontiac that I need a sending unit for and I was also wanting to know if a 55-57 Chevy was the same or would work? Any help would be appreciated. Thanks

[The Hammer]

Here's what I've found on my '56..... I took my sending unit out and it is not the same as the Chevy 55-57 units. However, it is very similar to the '58-60 chevy units. The ones that only have about 1.5" of tube past the float pivot. I scored one on ebay for about $45 shipped. Much better than the $75-99 that CPR charges you.

I got the 3/8" one because I plan on running fatter lines for more fuel. But they have a 5/16" one also. Or you can get the 3/8" one and just put a reducer fitting on.

Also due to the direction the tube on the unit bends, it may be necessary to put in an extra length of bent line to reach it or a section of rubber hose. Or try and bend the tube on the sending unit the other direction (I don't recommend this).

Not sure if it's the same for the '57 model. But I bet it is.

looks like this....

[The Hammer]

OK. I installed this unit this past weekend. You can make it work, but it takes some modification.

The mods you have to do are:

1. slightly bend the tube between the pivot and mounting flange
2. Re-drill the mounting holes to line up with the tank holes
3. Dent the tank so that there is clearance for the outlet tube
4. Use a rubber fuel line to connect back up to the fuel line. The unit outlet isn't threaded.

Also a tip..My try using some sealant around the gasket. Mine is slightly leaking around the gasket right now and I'm going to have to drop it and try to get it to reseal. Also connect the sending unit wire before mounting the tank. If you don't, it's real hard to access the terminal stud after it's up.

Otherwise, it works just fine.

I have some pics if anybody really wants to see them.