Hey guys I am new to this forum so please don't bash if i say something wrong. I am hoping to get some help figuring out a weird problem I am having with my 1985 GMC - so here it goes, here's what i have and a short history on what ive do to do the truck so far
I picked up 1985 GMC Sierra Classic 4x4 K1500 a while back to restore. This is really a rolling restoration where most of the restore focus will be put on the interior at this point. The Motor is a Crate motor replaced years ago and still in very good condition. Stock tranny but was rebuilt years ago as well and very good condition as well. Body is in very good condition. Interior needs a lot of work.
the front end suspension is almost all new, replaced rotors and pads, bearings all tie rods leaf springs with Rough Country 4" lift kit. etc.
ive replaced a lot of other mechanical parts so the truck is in really good running condition. So here's the problem I am experiencing now
the other day i started noticing a rubbing sound that seemed to increase with speed. this seems to get progressively worse and seems to be speed related not RPM related. sounds a lot like the metal tab on brake pads rubbing against rotor, but its not that for sure because all of that is new, but that's what it sounds like. and its not consistent with a full tire rotation, the rapid frequency is much faster than full tire rotation, but the frequency of the rubbing sound increases with speed and i only start to here it when i get above 10 or 15mph. it also seems like there's an electrical short as well because when the rubbing the radio would cut out on acceleration then start playing again after i let off the gas, weird i know, i did some work on the radio and thought that could be playing a role so i removed the radio altogether and pulled the radio fuse as well. after i pulled the radio it seemed to stop for a short distance only to start up again ... and now there's smoke coming from behind the dashboard and gauges, so something is definitely burning... but the strangest part is that it seems both electrical and mechanical .. Whatever is starting to burn up behind the gauges only smokes and burns from speed the faster i go the more smoke ... obviously i parked the truck and not driving now. I am just describing what i experienced coming back from the store. When smoke started coming out from behind the dash, i noticed it increased with speed until i stopped at a convenient store and started checking everything all over but couldn't find anything. With the truck parked but still running the smoke and burning stopped.
Hopefully i described the problem well where it makes since, but its almost like the faster the it goes the more voltage SOMETHING is getting and burning up. It doesn't seems to be RPM related either because i can sit parked and rev the motor and it doesn't smoke or make the rubbing sound.
Any ideas? i know this is old school truck with carburetor and most everything mechanical rather than computer or electronic....
Thanks in advance
-Trey
I picked up 1985 GMC Sierra Classic 4x4 K1500 a while back to restore. This is really a rolling restoration where most of the restore focus will be put on the interior at this point. The Motor is a Crate motor replaced years ago and still in very good condition. Stock tranny but was rebuilt years ago as well and very good condition as well. Body is in very good condition. Interior needs a lot of work.
the front end suspension is almost all new, replaced rotors and pads, bearings all tie rods leaf springs with Rough Country 4" lift kit. etc.
ive replaced a lot of other mechanical parts so the truck is in really good running condition. So here's the problem I am experiencing now
the other day i started noticing a rubbing sound that seemed to increase with speed. this seems to get progressively worse and seems to be speed related not RPM related. sounds a lot like the metal tab on brake pads rubbing against rotor, but its not that for sure because all of that is new, but that's what it sounds like. and its not consistent with a full tire rotation, the rapid frequency is much faster than full tire rotation, but the frequency of the rubbing sound increases with speed and i only start to here it when i get above 10 or 15mph. it also seems like there's an electrical short as well because when the rubbing the radio would cut out on acceleration then start playing again after i let off the gas, weird i know, i did some work on the radio and thought that could be playing a role so i removed the radio altogether and pulled the radio fuse as well. after i pulled the radio it seemed to stop for a short distance only to start up again ... and now there's smoke coming from behind the dashboard and gauges, so something is definitely burning... but the strangest part is that it seems both electrical and mechanical .. Whatever is starting to burn up behind the gauges only smokes and burns from speed the faster i go the more smoke ... obviously i parked the truck and not driving now. I am just describing what i experienced coming back from the store. When smoke started coming out from behind the dash, i noticed it increased with speed until i stopped at a convenient store and started checking everything all over but couldn't find anything. With the truck parked but still running the smoke and burning stopped.
Hopefully i described the problem well where it makes since, but its almost like the faster the it goes the more voltage SOMETHING is getting and burning up. It doesn't seems to be RPM related either because i can sit parked and rev the motor and it doesn't smoke or make the rubbing sound.
Any ideas? i know this is old school truck with carburetor and most everything mechanical rather than computer or electronic....
Thanks in advance
-Trey
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