Was wondering if anyone else is experiencing this. When the truck is in gear, i get small rattling sound coming from the motor. When i'm driving, i'll accelerate and when i take my foot off the gas i'll hear this rattling, it also happens when it changes gears. Its weird and I can't pin point where the hell its coming from. Any ideas??

------------------
2000 Silver Lightning
2935/4966
Best 1/4, 13.91 @ 99.52 mph Stock
1994 White Taurus SHO

 

Cats?

------------------
Red '00 Lightning,
Power Surge Performance enhanced,
Sound effects provided by Flowmaster,
375 RWHP,
445 RWTQ,
13.227@103.55
Track Videos

 

Got an aftermarket intake?

 

YES YES YES YES,

I have had this same problem.I thought it might have been my lower bearings but i cannot duplicate it while not in gear.This is exactly what has happened to me.It also sounds like the valves are all rattling!!. Finally someone with the same problem.I have a few questions and a few answers.

1. Do you have a chip? The rerason i ask is,I have onlt noticed it while chip is in.Im not saying it goes away but,I only notice because the truck takes longer to shift if you accelerate and then let off to shift.

2 I brought it to my dealer and they said they heard it. They replaced both my belts and said it went away.I havnt put my chip back in or drove it do to winter but this could be fixed already and I dont know.There is a tsb on this rattling and belts.The lower pully must come off.Its worth a try.It is a very disturbing sound.

 

Thanks for the details lightningquick. Aside from my mufflers the truck is stock. no chip, nothing. I have an appontment next week to get it hopefully correct the problem.

------------------
2000 Silver Lightning
2935/4966
Best 1/4, 13.91 @ 99.52 mph Stock
1994 White Taurus SHO

 

it happens on my 00 with the air compressor on and in gear before it was chipped. i was thinking maybe i pulled the idle down to low and it was back lashing some. i will have to check into the belts but what about the lower pulley?

 

the noise i am talking about only happens right before thr shift points.It is a rattling that sounds like valves or a lower rattle but is not the case.I really think it was just the belts.

the lower pully must come off to replace the belt.

Ill know for sure in the spring.

it is good to know it is no big deal and somebody else has this ecact same problem

 

I have a rattling noise before shift at about 3000 rpm's but only when the engine is cold. Goes away after warm up. Some say it is piston slap. It doesn't sound that deep to me. Sounds more like valvetrain noise. Have also heard it a couple of times on cold start up at idle but only for a few seconds in real cold weather (40 or less in Texas thats real cold). Steve

 

On cold morning after the truck has set for a couple days I hear a funny noise that sounds like an air compressor taking off. The dealer can't get it to do the same thing.

------------------
1999 Red SVT Lightning
#3466 of 4000
NLOC #428
99 Grand Prix GTP Red