Got a vibration...at 55MPH - The 1947 - Present Chevrolet & GMC Truck Message Board Network

suburban99 · 04-19-2016, 12:31 PM

LS swapped 62, 4L60E one piece driveshaft, 2-1/2 drop spindles with 1 coil cut, 4 or 5" drop springs in the rear can't remember...I get a vibration at 55mph that goes away at 60mph...Truck is smooth (for a 54 year old truck) other than at this speed. All u-joints are new. Tranny shifts good. Could it be my driveshaft? Why would it not vibrate at other speeds? Thanks

BR3W CITY · 04-19-2016, 03:54 PM

Pinion angles are the first thing I generally look at with vibrations. 5mph is a pretty narrow window, so its completely fine at 1-54 and then like 60-80?

If its the driveshaft, you can find an empty space of road and get up to 55, pop the truck in neutral and see if the vibration goes away. If its a wheel/tire/brake issue, it will persist. Might be a bit tricky if you only have a 5mph window, so just use caution.

suburban99 · 05-19-2016, 05:24 PM

Ok been busy these last few weeks:
Tried to pop it in neutral at 55 and shake is still there...

Found a kinked brake line for passenger side disc that was not allowing passenger side calliper to open.-changed it.
New front shocks as old ones were toast
New rear shocks

Front end seems to jump around right around 50-60 now. Smooths out a bit but not completely... Alignment? Truck has a 78 disc front end...

storm9c1 · 05-19-2016, 10:49 PM

Front end jumps around? Sounds like tire balance to me. If they are the same size, swap them with the rears and see if front end gets better.

If you suspect alignment, that wouldn't hurt either, get it done. I'd also look for play in steering system, ball joints, etc.

There could still be a driveshaft issue lurking here too. Been there, done that many times.

suburban99 · 05-20-2016, 11:04 AM

Dropped off the front tires at the tire shop today to see if that's the issue.

suburban99 · 05-28-2016, 11:32 AM

Rally wheels are balanced but bent...apparently this is the cause of the vibration...they came with the truck so I don't know origin.

04-19-2016, 12:31 PM	#1
suburban99 Registered User Join Date: May 2014 Location: Mission BC Posts: 452	Got a vibration...at 55MPH LS swapped 62, 4L60E one piece driveshaft, 2-1/2 drop spindles with 1 coil cut, 4 or 5" drop springs in the rear can't remember...I get a vibration at 55mph that goes away at 60mph...Truck is smooth (for a 54 year old truck) other than at this speed. All u-joints are new. Tranny shifts good. Could it be my driveshaft? Why would it not vibrate at other speeds? Thanks __________________ 1962 C10 Longbox LS 5.3 4L60E----Sold$$ 2014 Ram 4x4 3500 Laramie Diesel..Momma's truck 2015 Ram 4x4 1500 1997 Boxster. 1972 K10 Custom Deluxe LS 6.0 1950 GMC 3100 S10 & LS swapped

04-19-2016, 03:54 PM	#2
BR3W CITY meowMEOWmeowMEOW Join Date: Sep 2009 Location: MKE WI Posts: 7,128	Re: Got a vibration...at 55MPH Pinion angles are the first thing I generally look at with vibrations. 5mph is a pretty narrow window, so its completely fine at 1-54 and then like 60-80? If its the driveshaft, you can find an empty space of road and get up to 55, pop the truck in neutral and see if the vibration goes away. If its a wheel/tire/brake issue, it will persist. Might be a bit tricky if you only have a 5mph window, so just use caution. __________________ *'66 Short Step / SD Tuned / Big Cam LQ4 / Backhalfed /Built 4l80e / #REBUILDEVERYTHING* MY BUILD THE H8RDCPTR //\\ MY YOUTUBE CHANNEL REV J HD

05-19-2016, 05:24 PM	#3
suburban99 Registered User Join Date: May 2014 Location: Mission BC Posts: 452	Re: Got a vibration...at 55MPH Ok been busy these last few weeks: Tried to pop it in neutral at 55 and shake is still there... Found a kinked brake line for passenger side disc that was not allowing passenger side calliper to open.-changed it. New front shocks as old ones were toast New rear shocks Front end seems to jump around right around 50-60 now. Smooths out a bit but not completely... Alignment? Truck has a 78 disc front end... __________________ 1962 C10 Longbox LS 5.3 4L60E----Sold$$ 2014 Ram 4x4 3500 Laramie Diesel..Momma's truck 2015 Ram 4x4 1500 1997 Boxster. 1972 K10 Custom Deluxe LS 6.0 1950 GMC 3100 S10 & LS swapped

05-19-2016, 10:49 PM	#4
storm9c1 * That's interesting * Join Date: Oct 2008 Location: Pittsburgh, PA Posts: 2,772	Re: Got a vibration...at 55MPH Front end jumps around? Sounds like tire balance to me. If they are the same size, swap them with the rears and see if front end gets better. If you suspect alignment, that wouldn't hurt either, get it done. I'd also look for play in steering system, ball joints, etc. There could still be a driveshaft issue lurking here too. Been there, done that many times. __________________ Tom Chevy by day... 1969 Chevy C30 Rollback Tow Truck -- 383 stroker, 4L80E 2011 Chevy Caprice PPV 9C3 6.0L 1995 Chevy Caprice 9C1 1994 Chevy Caprice 9C1 #3 1995 Chevy Caprice Wagon #2 1995 Chevy Impala SS Mopar by night... 1969 Dodge Charger 1972 Chrysler Newport 2dr Hardtop (27K miles) Plus others...

05-20-2016, 11:04 AM	#5
suburban99 Registered User Join Date: May 2014 Location: Mission BC Posts: 452	Re: Got a vibration...at 55MPH Dropped off the front tires at the tire shop today to see if that's the issue. __________________ 1962 C10 Longbox LS 5.3 4L60E----Sold$$ 2014 Ram 4x4 3500 Laramie Diesel..Momma's truck 2015 Ram 4x4 1500 1997 Boxster. 1972 K10 Custom Deluxe LS 6.0 1950 GMC 3100 S10 & LS swapped

05-28-2016, 11:32 AM	#6
suburban99 Registered User Join Date: May 2014 Location: Mission BC Posts: 452	Re: Got a vibration...at 55MPH Rally wheels are balanced but bent...apparently this is the cause of the vibration...they came with the truck so I don't know origin. __________________ 1962 C10 Longbox LS 5.3 4L60E----Sold$$ 2014 Ram 4x4 3500 Laramie Diesel..Momma's truck 2015 Ram 4x4 1500 1997 Boxster. 1972 K10 Custom Deluxe LS 6.0 1950 GMC 3100 S10 & LS swapped



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