'99 XLT front end rattle / vibration

[762mm]

I've searched this time and time again, but can't find a definitive answer..
I have a major pain in the behind with a metallic-like rattle under my '99 XLT, it seems to be coming from the front of the truck, possibly exhaust-related (but I can't find the exact location visually).

Ford has pulled the SOHC engine out of the truck a few month ago to replace the cam tensioner (front only, they inspected the rear and it was "ok") because it was causing a diesel-like sound/rattle in idle and under light acceleration when cold. The problem hasn't returned, and the rattle I have now is only audible when the RPMs drop very low in idle (sounds like a loose piece of metal in a tin can). I still hope it's not coming from the engine itself but rather the exhaust - I've read on the forum about a "Y" bracket that can be placed between the transmission and exhaust to fix a similar rattling problem, but I couldn't find any specifics about it (writeup, pictures, etc..).

Any help would be gratly appreciated, thanks a million in advance... This has been a pain in the a** for me for months now, as it always occurs when I stop at red lights, intersections or park the truck in a parking lot (nice truck, awful rattle).

P.S. Plugs, wires, MAF, IAC, injectors have all been either replaced or cleaned very recently, nothing has helped.

 

[Chubbyfresh]

Have you checked the heat sheild on the Cat? I had a similar problem and it turned out to be a broken weld on the heat shield - I just tore the whole hting off and havn't had any problems since.

I also had a similar rattle though at high rpms (2500+) which turned out to be an engine ping -- some sea foam fixed that

A search on either sea foam or cat heat shield should bring up a lot of threads

hope this helps

 

[nailhead_sled]

Most likely a heat shield rattle. Crawl underneath and give the shields a shake and/or take a long screwdriver and give them a few taps.

 

[kworzy]

if your having a rattling sound coming from your motor is bad, when its only at low rpm thats worse, i had the same problem on my dirt bike, and it turned out to be piston slap, but thats a dirt bike, not a truck, but i thought i'd run that by ya so you can investigate it further, hope i'm wrong

 

[Hartman]

if your having a rattling sound coming from your motor is bad, when its only at low rpm thats worse, i had the same problem on my dirt bike, and it turned out to be piston slap, but thats a dirt bike, not a truck, but i thought i'd run that by ya so you can investigate it further, hope i'm wrong

Don't worry, you are.

 

[Diddy74]

I'm not sure if we suffered from the same shake rattle and roll, I also had an annoying rattling and mettalic grinding coming from the front of my 99 xlt. Every mechanic I took it too went for the usual suspects exhaust,cat shield, etc. Eventually one guy found a bolt broke off the right front break shield which caused it to rub against the rotor(grinding)and since it was off, every little bump or vibration caused that god awful rattle!

 

[762mm]

Thanks everyone for your replies. When time allows, I'll put the front up on ramps and try to do a complete verification of everything that may be loose - I did that before (a few months ago), but for some reason then I drove onto the ramps, the rattle has almost completely stopped and I couldn't find anything... I could have sworn that it almost sounded like a loose piece of metal inside the exhaust somewhere, but I couldn't be 100% sure. When I get a day off, I'll do the check again and will post the results.

P.S. I have done a Seafoam treatment recently and it hasn't helped with the rattle. Ford has changed/inspected the timing and cam chain tensioners recently, so I doubt it's coming from the engine (plus it sounds like it's something right underneath the truck - it goes away instantly when I give it a little gas, therefore it's probably due to idle vibration on some metallic part).