Lift + Driveshaft = Clunk issues

[frankcal]

So I have a question for the experts on here, first off thanks for reading and hopefully giving some input on the the issue.

Since I lifted the sport I've been experiencing some clunking when coming to a start or stop. Looked up on it and determined the u joints were the issue. Changed those out and still experienced the problem but slightly faded. I checked the drive shaft for play and am not experiencing any, everything is tight and good. So today I read another thread about a driveshaft spacer to correct the driveshaft. I inspected the truck and noticed that the drive shaft was leaking were it connects to the trans. Trans fluid level is fine, seems like a slow leak.

I ordered a spacer off of ebay to hopefully correct the issues, but am a little more worried about the trans. I want to know if this badly effected the trans or blew some kinda seal. Or if it just means that the driveshaft was too short that why oil was able to leak out of the trans. Also does it seem like the spacer would correct the issue or is there something else that I should be looking at.

I took some pics of the yoke and it seems like its about 5/8 slipped out from the oil markings on it.


Do any of these look normal or does it seem like this could be the culprit of my infamous clunk.

Also do the splines on the yoke going into the trans and diff need grease on them, I didn't see any on there when I switched out the u joints so I didn't put any in.

 

[Sogsnakebite]

Have u checked the slip joint n the shaft to see if it's seized ? I haven't had any drive shaft problems other than joints needing to be changed and a stuck slip joint needing greased

 

[swshawaii]

Ditto slip joint aka yoke. 4WD correct?
http://www.explorerforum.com/forums/showthread.php?t=79594

Driveshaft Slip Yoke Disassembly and Assembly
https://www.scribd.com/doc/267374167/Driveshaft-Slip-Yoke-Disassembly-and-Assembly

 

[frankcal]

Thanks for the advice I thought the exact same thing ad's even crawled under to look for it, but its a 2wd so the slip joint is a no go

 

[frankcal]

So to update, I purchased the spacer and should be here on monday and will be installed on delivery day. Hopefully it solves the issue of the clunk.

Does any one know if the yokes need grease on the spline that goes into the trans and rear diff?

 

[Josh C.]

The 2nd picture looks like there is a hole in the black rubber seal(?) on the diff end.

Have you disconnected the drive shaft and spun things by hand to try to recreate the sound?

Something I went through before my Sport died, check the body mount bushings. A clunking sound eluded me for years and it ended up being my body mounts.

Good luck

 

[jenren81]

So to update, I purchased the spacer and should be here on monday and will be installed on delivery day. Hopefully it solves the issue of the clunk.

Does any one know if the yokes need grease on the spline that goes into the trans and rear diff?

how did this turn out for you?? i've had a clunk that happens when coming to a complete stop or letting off the brake from a complete stop for awhile now, kind of intermittent but noticable...

 

[frankcal]

Ok so to update finally. I originally bought a spacer off ebay that I had got a link off of from the forum, that didnt work. That spacer was too small and the holes didnt line up right.
I got a fabtech one for an f150. I just installed it a few days ago and so far it seems to be helping. The sound is definitely more muted and not there as much. It helped the issue buts its still faintly there. But for me its good enough because I dont want to go with a bigger spacer necause of the plunge and dont want it to go too deep into the transmission.
As for my body mounts, the passenger side is weathered so ill change them in a while. My tranmsission mount is weathered too, which another member pointed me too. So those bushings will be changed eventually, just skeptical of the body mounts from reading all the threads here.

 

[fast_dave]

frankcal -

I have a '98 4WD Sport, so this may not apply to you, but I'll throw it out there anyway.

On my rear drive shaft, there is a slip joint covered by a rubber bellows, and sealed on both ends by stainless steel bands.

FORD did NOT provide a "zerk fitting" near the slip joint, so as to allow periodic lubrication.

Frequently, the grease in the bellows leaks out and/or hardens, and the driveshaft starts making a loud "tink" noise on start and stop.

If you do have a rubber bellows on your rear drive shaft - try the following.

Cut off the FRONT stainless steel band, and push the bellows back towards the diff, and either by hand or grease gun, lubricate the splines with grease. To clarify - whatever you can do to get grease in there - DO IT!

When done, pull the bellows forward, and use two heavy-duty zip ties, with the "locks" orientated 180 degrees apart to re-seal the front of the bellows (for "twice" the security as well as balancing).

Normal driving will spread the grease around, You could always go to a parking lot that has high speed bumps to compress and decompress the suspension. That "action" will allow the grease to spread along the splines, as the driveshaft shortens and lengthens.

HTH and report back!

 

[boominXplorer]

Ford sells special lube for driveshaft clunk and grunt noises. It's made specifically for slip joints but I have used it on 2wd splines with great results. Just squirt some in the driveshaft end and spread into the splines with your fingers and reinstall.

 

[frankcal]

Ok so I dont have that bellow, I looked for it a few times thinking I was missing something since that was all I could find when searching on here. But being that im 2wd I have no slip joint or bellow, just the shaft with splines on one end and a flange on the other.

But, could I put grease on the splines that go into the transmission?
I didnt see any grease on the splines when I originally changed the ujoints. When I put on the spacer I wanted to stick some grease on there but was too skeptical thinking that grease would somehow work its way into the tranny.

Thank you guys for your suggestions, even though they don't specifically apply to me im sure some one will come across this thread that will learn from it.

 

[boominXplorer]

Ok so I dont have that bellow, I looked for it a few times thinking I was missing something since that was all I could find when searching on here. But being that im 2wd I have no slip joint or bellow, just the shaft with splines on one end and a flange on the other.

But, could I put grease on the splines that go into the transmission?
I didnt see any grease on the splines when I originally changed the ujoints. When I put on the spacer I wanted to stick some grease on there but was too skeptical thinking that grease would somehow work its way into the tranny.

Thank you guys for your suggestions, even though they don't specifically apply to me im sure some one will come across this thread that will learn from it.

Yes you can use the grease I posted above. I have used it a few times in slip yokes with good success.

 

[fast_dave]

frankcal,

No prob - someone will find the thread and utilize the info.

If you pull your front yoke, have a large diameter pan close and a lot of rags, because auto trans fluid will go everywhere

Just saying - your rear trans seal needs to be replaced to properly fix that auto trans fluid leak.

This is a very simple "Auto 101" repair that you could do yourself.
Going slow, maybe a 1 and 1/2 hour repair in total.
All the info is out there - this forum (Modified and Stock), the Interweb, Youtube, etc.
It's going on Full Blast Summer in the PRK, and the hot weather means the leak will only worsen.

And hey - when replacing the rear transmission seal, it wouldn't hurt to apply some elbow grease utilizing emery cloth to polish and remove the layer of rust on the outside of that yoke that inserts into the rear seal on the transmission.

The rust on the outside of the yoke will continue to wear out your old seal, as well as quickly wear out a new seal, as the driveshaft front yoke travels inwards and outwards.

Good luck and YMMV

 

[frankcal]

Thanks for that advise dave, I'll definitely look into it. I didn't even think that there could be an issue with the seal, I just thought it was leaking because the shaft was loose, I'm going to be keeping an eye on it too see if it is leaking still with the spacer. I hear you though on that rust, I'll be doing that when I get some free time next week.

So far the spacer seems to be doing the job well, no more clunking when starting to go.