Fuel Filter Replacement 5.3 Flex Fuel

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scottg918514

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Ok, hopefully I can help some of you before you tackle what is supposed to be an easy job.

I have an '03 LS (for sale :)) and a new to me '03 Z71. I'm in the process of doing all the maintanence on the Z71. Today: replace the fuel filter, with the new one I got from Rockauto. Easy, did this on my LS.

I get underneath the Z71, whoops, my new filter doesn't look the same. Damn, I must have a Flex Fuel 5.3. Honestly, in '03 they weren't badged like they are now, so I didn't even think about it. BTW, if the 8th digit in your VIN is a Z you have a Flex Fuel truck (at least for '03).

No big deal, run down to Advanced and get the right filter. Unlike the standard fuel trucks, this filter has a 16mm threaded coupler at one end (both ends in standard fuel truck) and a quick connect at the other end (front). It should be called Quick Connet-Pain in the ASS to Disconnect.

Unfortunately instructions for this filter are not in the Haynes manual, but do follow all the other instructions, like de-pressurizing the fuel system.

The problem lies in the fact that you can't get a fuel line disconnect tool between the filter body and the fuel line. Dumb! Anyway, you need to cut the front nipple off the front of the old filter. I used a saws-all (yes, I said it, an electrical tool on a fuel system). I'm still here, but I recommend a good strong pair of tin snips, which I didn't have.

After cutting and removing the filter, you can now use your fuel line disconnect tool the remove the last bit of the fuel filter nipple from the fuel line. Done, now time to install tne new filter.

Mine came with a plastic white clip around the nipple. I believe this would help you disconnect next time, the problem is you can't get the filter to connect with it on. Get rid of it.

Connect new filter and go, done. Damn, that was way more difficult then it should have been.
 

electro

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For VIN:Z peeps this is some great info!

Cut the pointy end of the filter and use your fuel line disconnect tool as its supposed to be used. Jam it in there and pop that cut off out.

Remove the plastic tab/collar on the new filter, its not needed.

Just confirming all this info.

Thanks Scott it all worked for me.

I vote sticky. FLEX Fuel - Fuel Filter removal.
 

jrdecat

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Resurrected thread!!!

Dealt with this crap for about 2 hours. How hard can a fuel filter be? Too bad I didn't read this beforehand! I ruined a disconnect tool in the process.
 

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