"thudding" sound??

[itslikewhooa]

Ok so lately I've been hearing a sound coming from the rear of the truck although I cant be absolutely certain because it only happens when I'm driving... I took it to a trans. shop near me and had them take it for a drive.... they said it wasn't the trans. and that the sound was normal... well I know that a loud thud noise isn't normal. so hears the problem

when driving usually around 30 -50 mph if I take my foot off the gas and then tap the gas, there is a loud "thud" noise, again I believe coming from the rear of the truck. during normal take off from a stop through all gears it doesn't make the noise at all, and shifts fine and smooth.

the trans. place put it on there lift and said everything was tight and nothing seemed loose. I'm going to jack my truck up my self and double check them. because they also said the noise was normal.

could it be something in the rear diff. ?..... I read somewhere that the axle sleeves are only pressed in and not welded...I do tow some heavy weight behind the truck could those have loosened up?... I'm going to check the u joints myself. or is it something I'm not even thinking of....

any help would be appreciated

thanks in advance -Ross-

 

[itslikewhooa]

I forgot to put in truck specs.....

2000 explorer
AWD 5.0 v8
about 180,000 miles

 

[gonenuke]

When its jacked up check out your u joints. When mine were going out on a 92x it felt like a transmission problem.

 

[yavapaires]

Ok so lately I've been hearing a sound coming from the rear of the truck although I cant be absolutely certain because it only happens when I'm driving... I took it to a trans. shop near me and had them take it for a drive.... they said it wasn't the trans. and that the sound was normal... well I know that a loud thud noise isn't normal. so hears the problem

when driving usually around 30 -50 mph if I take my foot off the gas and then tap the gas, there is a loud "thud" noise, again I believe coming from the rear of the truck. during normal take off from a stop through all gears it doesn't make the noise at all, and shifts fine and smooth.

the trans. place put it on there lift and said everything was tight and nothing seemed loose. I'm going to jack my truck up my self and double check them. because they also said the noise was normal.

could it be something in the rear diff. ?..... I read somewhere that the axle sleeves are only pressed in and not welded...I do tow some heavy weight behind the truck could those have loosened up?... I'm going to check the u joints myself. or is it something I'm not even thinking of....

any help would be appreciated

thanks in advance -Ross-

Along with checking the u-joints, check the slip yoke. Sounds like a dry slip joint maybe. While you have the drive shaft out, turn the yoke to the rear end sharply back and forth, listening and feeling for the noise. Could also be a loose yoke, or pinion bearing.