Need to fix driveline clunk

[Paisano]

92' Ranger XLT with 2.9 V6.
I have the textbook clunk or thump when starting from a dead stop. It's getting worse and sometimes I get a second thump after the initial thump while accelerating.
I spent time looking at everything under the truck and I didn't see anything. I'm pretty sure the problem is in the area of drive shaft slip yoke/transfer case.
I have the 2-piece driveshaft.

The first I'll check is the slip yoke. I've done some reading. But I have a couple questions.

1. Do the slip yoke and driveshaft splines need lubricating on my make and model?
2. If I disconnect the driveshaft companion flange at the differential, can I then just pull the driveshaft away from the transfer case to expose the splines?
3. If I need a new slip yoke, I'm not able to determine which one I need. Do I just count splines and take measurements to select the one I need ?

 

[franklin2]

You must have a supercab 2wd? That is the only 2 piece driveshaft I see that year. They did make a 1 piece also.

If you do have a two piece, then you have a support bearing or carrier bearing mounted on a crossmember. Is that ok? They are usually mounted in rubber and the rubber breaks up and fails.

 

[Ramcharger90]

Carrier bearing as stated above or u joints need replaced. But what I'm really thinking it is..... the rear is about to let go Go under there and pull up and down and side to side near the pinion on the deive shaft and do it again near the front diff pinion. But it sounds like its time to remove the 7.5 rear and get an 8.8 if it doesn't have one already.


Slip yoke wont do that clunk it is such a tight mesh how the splines are cut and if you pull it apart you better make sure you put it together within like one spline of ear to ear or it will shake horrible from being out of balance.

 

[Paisano]

I have the Supercab with 4WD. Single cardan 2-piece drive shaft.
I checked everything you mentioned above. And I don't see a problem in those areas. I also installed a rebuilt 8.8 complete rear axle assembly less than 2 years ago. Maybe it's not the the slip yoke. But why do you rule out the slip yoke altogether? I don't see what a tight spline fit has to do with it. Isn't it the forward and rearward lack of play, from insufficient lubrication that might cause the thump? I can check all this again.

 

[franklin2]

Make sure you are chocking the front tires, lifting up both back tires off the ground, and putting the transmission in neutral with the parking brake off when you are pulling and twisting on things back there. You need to take all the strain off the driveline when checking it.

 

[Paisano]

The rubber accordion boot over the driveshaft splines is torn through. I have to disconnect the driveshaft anyway. This will give me another opportunity to inspect everything, replace the boot, and grease the splines next weekend.

I have to take my truck in for the third time tomorrow morning for warranty repair on the transmission.

 

[ElectraRider]

I had that thumping in my 98 and my 2000 , drilled a hole in where the slip spline ended tapped and screwed in a grease fitting pumped in about a half tube of grease and no more thumping on take off but do check your universal joints just to be sure.

 

[Paisano]

Ok. I like that grease fitting idea. Do you remember what thread size you tapped in?
My slip yoke has what appears to be a little plastic or rubber cap or plug. What is this for?

 

[franklin2]

Ok. I like that grease fitting idea. Do you remember what thread size you tapped in?
My slip yoke has what appears to be a little plastic or rubber cap or plug. What is this for?

Buy the grease fitting first. Then you will know what size thread you need. They come in several different sizes, you most likely want the smaller size, 1/4-28 is a common size.

 

[Ramcharger90]

I have had trucks that were caked in mud, sat in a lake for a few weeks and drove them out of the fields after they sat for a decade plus..... granted they were old power wagons and Ramchargers but the only time I have ever heard what you described was when the 7.5 rear was going bad in my 98 ranger... but I guess it is possible.

 

[Paisano]

Well. I have to remove the driveshaft anyway. That would be a good time to check for excessive play in the rear axle gear set and also grease those splines.
I'll pick up a grease fitting also. I'll probably have to use some type of universal accordion boot I can cut to size...possibly a shock absorber boot or something tapered at both ends. I am still looking online.

It's a pain in the neck trying to find parts for this old truck.

 

[Paisano]

I have a grease fitting assortment and a universal rubber accordion boot. And I already have a thread tap tool set. Will the addition of a grease fitting to the slip yoke cause an imbalance issue with the drive shaft?

 

[alwaysFlOoReD]

I'm guessing not. The metal you remove drilling and tapping will be about equal to the fitting and grease.

 

[Paisano]

Ok.That kinda' makes sense............one cancels the other out.
I wanted to do this tomorrow. But it might be better if I put it off for a few days. I have to take the truck in for the 4th time to the transmission shop on Monday.

I'm on vacation till 12/8. So I have some time to get caught up on a few tasks.

Is this pulling the driveshaft and greasing the splines fairly simple with 2 hours or less of labor...............just remove the bolts at rear axle companion flange and pull driveshaft rearward out of the slip yoke ?

 

[Josh B]

I am not sure how you marked it off the first time, but hopefully it was marked off complete front to back and back to front again leaving no room for error when reassembling it. I like a carpenters crayon for marking it with, you can get red, yellow, white, or others too I suppose

If you ever have to talk to Ford about parts or anything, that "Center bearing" has become its new name, seems some bearing in the transmission took the carrier bearings name away