Clunking from rear

[DirtDemon85]

The other day i took my truck offroading for the first time of the winter in the snow, well i had it in 4wd the entire time until i got back onto the streets i put it in 2wd. Well on the way home i got this awful thumping coming from the rear of the car, not sure what it is... it only happens when i let off the accelerator. and coast a little bit at any speed even while hitting the brakes, Once i hit the gas the noise stops. 4wd still engages so i dont know if its that, nothing seems to be loose underneath any help would greatly be appreciated

 

[BrooklynBay]

It's most likely the rear U joint which is near the differential.

 

[DirtDemon85]

Thanks for the help im gonna check it out

 

[toypaseo]

slip joint might need greasing

 

[DirtDemon85]

Ok well... bad news i was driving today and there was a loud bang, well i had to coast to a stop, its like my cars permanently in neutral however i can shift to reverse and 4wd but the car wont move it just makes a hell of alot of noise sounds like from the rear end... Im hoping it is a u joint but is it possible my rear gears are shot?

 

[BrooklynBay]

That unfortunately sounds like the differential gears. I've gone through that a few times on my 88.

 

[DirtDemon85]

I just did rear gears on my 04 mustang gt and put 4.10's in it, would the gears i took out 3.73's work or is that a differnt spline count?

 

[BrooklynBay]

They would have the be the same differential to match in size. What brand of gears did you previously use?

 

[DirtDemon85]

I took the rear end cover off and found that the spider gears were snaped in half, the ring and pinion seem to be fine no chips or anything. Is there a spider gear kit i can get? or maybe a pinion service pack? Its the 31 spline 3.73 8.8 ive been looking but cant find much except on the bronco graveyard website and i dont know if that would work because it says for up to a 96 bronco

 

[MustangAndy]

I took the rear end cover off and found that the spider gears were snaped in half, the ring and pinion seem to be fine no chips or anything......

Been there. Blew the spiders on my 02 'Stang. Foward was bad, reverse was just plain horrible. Cost me 'bout $500 to fix .My mechanic got the parts from a Ford dealer. He also had to replace the ABS sensors since they were rusted in.

 

[Redneck0907]

I have the same clunk, im pretty sure its in my transfer case though, the rear output shaft is known for warping making the round hole around the bearing to become oval. luckly for my sake i havent lost my gears yet. search for a 4405 on here and look for stuff about that. I found mine by trying to fix a rattle. i happened to hit the drive shaft near the t-case and realized it moved about a 1/8 of an inch. This also explains the vibration i get at 70-75 mph. hope this helps!

 

[DirtDemon85]

Well after ordering the parts from summit and doing the work in my drivway it cost me 200$ Total and about 2 hours of work, i was forced to buy the spider gear rebuild kit, a new ring and pinion and a gasket w/ the fluid... it was a very simple install thankgod besides having to measure the backlash on the ring gear but it didnt take long with the right tools Thanks for the help everyone

 

[DirtDemon85]

Well... I hate to say it... Gone AGAIN! Coming home tonight i hear a thud and then i lost driving ability... get outta the car and find that the gears are gone again and this time they put a nice big hole in the side of the diff. cover... Thank god Superior Axles and Gears has a 2 year warrenty... Could there possilbly be somthing else thats throwing my gears this fast? Something out of alignment or somthing?

 

[BrooklynBay]

Maybe the gears are too far apart, and only mesh together by the tips. You might need to add some spacers to get them to go closer together.

 

[DirtDemon85]

The last time the gears went, the center pin in the carrier ovaled out its opening so its not a tight fit anymore and makes the gears mash when rotated... Is there anyplace to find a used or cheap opened Dif. Carrier? The closest i can find is a limited slip for free out of another explorer, but id have to rebuild it