Still getting noise/vibration

[sparks57]

A while back I was complaining that my go pedal vibrates a lot going past 2k rpm.



My truck gets really noisy, and my go pedal vibrates as I am passing over 1900-2200 rpms, then smooths out again and gets real quiet, just like how my engine runs before 1900rpm.



This happens close to, or at, WOT... when I am not pushing it, it ussualy doesn't happen, or at least not as violently.



Does anyone else have this problem? I'm still trying to figure out what it is, becuase nobody else seems to have this problem is making me nervouse.



And no Daniel, beer and sorority girls won't fix it!



Can it be solved?

 

[JStraw]

Hey CB, check your motor mounts. By chance, does the brake pedal vibrate or anything else? What do you mean by 'it gets real noisey'? need more info.

 

[sparks57]

I don't know if it's the exhaust, engine, or injection pump... but there is just a lot of racket.



I think it's the injection pump... but I'm not sure.



I'm ussualy not holding the break pedal while I'm accelerating past 2000... but I'll check next time.

 

[JStraw]

I understand about 'not holding the break pedal while I'm accelerating past 2000', I should have mentioned to 'lightly' place foot on pedal. lol



Well... the exhuast would be easy to check to see if its loose, as well as inspecting the IP mounting. Grab hold and shake like a wild man on a caffiene high



Part that gets me is the vibrating pedal. It should be dead smooth.

 

[BCook1]

Check for binding u joints

Greetings,

My truck also has a shudder at about the 2000 mark but it is slight and only comes on when on it hard. It feels like a very even clutch slippage but it is not. Did it with both old and new clutch. Try backing up floored a couple times. If a rear joint is binding this will force it into a position it usually does not see. If you hear squeeking as you start forward again - a joint is sticking - CTD might cover up the squeek so start out easy. I had a sticky rear joint and just put new grease in the caps and reseated them and the shudder was diminished. It is still there a little though. Does anyone know of a poly hanger bushing for these trucks? I think these are a source of many driveline problems.

 

[sparks57]

I've been checking all my u-joints and they all seem fine.



My shudder seems to be just like yours...

 

[BCook1]

More questions

If it turns out to be your injector pump, please let me know. My mileage sucks. 10 towing in good weather. Have seen as low as 8. 7 into the wind, winter, towing, with blended fuel. If your pump is going and not providing proper metering at a given rpm that could be the problem. What is you mileage. I have tried every thing I can think of short of replacing the pump and no improvement - in fact my mileage has gone down. My shudder is not always there. I will try to pinpoint exactly the circumstances under which it happens. If it increases with outside temp or warm up of vehicle it could very well be axle wrap. Springs and shocks lose some control as they heat up. Check the hanger bearing - under load these things distort greatly and in effect make your two piece driveshaft act like a warped one piece.

 

[sparks57]

Last time I checked my mileage, I got 23mpg. That was a few months ago.



My pump seems ok... I can pull 2800rpms and I have a lot of power...

 

[Stomp]

Hey I don't want to scare you, but I had a noise and a little vibration more of a whine though first time it happened I shot my pinion teeth through the back cover. I completely went through the rear end and replaced everything with better parts and it decided to blow up again about 75,000 miles later and then the last time I heard it the old faithful Getrag decided to take a dump. The only reason that I didn't change the rear end and transmission to a Dana80 and a nv4500 is that I had a 91 parts pickup in the shop. Now I don't really have any more parts except the engine and the front axle. So if it happens again I will definitely change them out. Hope you have better luck than I did.



Stomp

 

[sparks57]

So maybe I should take a look at the rear end?

 

[Stomp]

If you have checked everything else it is always a possibility. My noise was traveling all the way to the cab through the drive terrain I could feel it in my shifter and my go foot



Stomp