I did the timing adavnce, about 1/8" and i notice a tad more rattle at idle. After pulling a load of scrap yesterday I now notice a rattle while drivinig. Its not super loud, its not a constant. but it seems like there is now a tad of rattle at 70 mph, around 2,000 rpm or so. I dont notice it when going through the gers, just with the windows up an at cruise speed.

Can the valves do this too? Cause Im willing to bet they were never adjusted

 

I'd check the jack mounted under the airbox.

 

I had a rattle like that. Drove me nuts for 2 weeks. I couldn't find it when not driving because it had to be the perfect RPM to make the noise. Turned out to be cracks in my slave cylinder cover around the bolt holes. Welded some reinforcement washers on and now no noise.

 

mine has the same thing maybe. It is a rattle/rumbe you can feel in the floorboards and footfeet from 2100-2250 rpms in 4th and 5th gears. I never have been able to track it down. I almost wonder if it is the tranny mounts or the ujoint on the rear of the tcase.

 

Mine too has a metalic vibration sound at about 1050 rpms no more no less and I've yet to find the dang thing

 

Sounds like a good time to check/set your valves.

 

i never have felt anything, and the truck doesnt skip a beat, but i do hear a tad of rattle. Maybe ill check them tonight

 

I had a chance while mounting my Boost gauge to go ahead and set the valves. I used the specs that Wanna gave, .009 and .018 and all were somewhat close, 2 of them where dead on, but WOW 1 exhaust valve was I swear a good 1/8" too loose, i reset it and now no more rattle.

If you are doing your valve adjustment for the first time, 2 words of caution.

1. blow all the dust and dirt away from in between the valve covers.

2. error a lil bit on the loose side when turning the pushrod, because when you torque the lock nut, it will spin the pushrod a lil bit too-setting the valve too tight.

Other than that its cake. I did the companion cylinder method, and it worked very good.