CV Joint Noise

I have 2000 Ford Windstar SEL with 131K miles on it.

Current condition: I am getting a thumping and vibration from the left front suspension. Noise and vibration is louder when turning left and disappears when turning right. Also, vibration is greater at higher speeds. I am thinking this is a CV joint issue on the left side. I have read the threads regarding grease injection and plan on trying that.

If the grease is not a cure how can I tell if the joints need rebuild/replace and which joint is the culprit inside or outside?

The outer comes with the drive axle and the inner is rebuildable per the Haynes manual. I want to make sure I have the parts at hand before I start removing pieces. Or should I do both the inner and outer together?

Thanks

The comments on grease needles and the like apply to tie rod ends and other suspension joints that have dust boots. I would not think it is a good practice to apply grease this way to drive shafts. The boots on drive shafts should be without cracks, splits, or punctures.

Drive shafts are rebuildable (I've done a few). It's a demanding, messy job. If you try it make sure you buy new boots and lubricant from Ford. Do not even waste your time if the boots have split...letting dirt get inside. You can now buy aftermarket rebuilt "exchanges" that work just fine. I never intend to rebuild another driveshaft. Check with AutoZone or any other parts store.

Make sure your problem is driveshafts. If the shaft boots are still in good shape... you may have wheel bearings or some other issue.

If the boots are in good shape what are some methods to diagnose the problem?

Finally got a chance to get a look underneath it. The wheel does not have any give to it when jacked up so I think the bearing is ok. The boots on the drive shaft both are in good shape with no apparent leaks or cracks. The van was in a cool garage for at least an 1.5 hours prior to inspection and the area on transmission housing where the inner CV connects was still hot - almost to hot to touch. Must be tranny issue, ouch!

Your method of diagnosis seems sound.
For further confirmation, is there a way that you can support the front wheels off ground and SAFELY get underneath? Parking brakes fully on, etc., etc. !!!
With the engine running and tranny in drive, you can use a length of hose to probe, as a stethoscope, around on tranny or on the drive shafts.

Please be safe!

One cheap thing to try....rotate the tires...fronts to the back, and the back to the front. Tires can look great and still cause thumping. If the problem goes away, or moves to the back, then you can have the ballance checked, etc.

Hi
If you decide it is the CV joint(s) you can replace the half-shaft with a remanufactured one for around $100 with a core trade. Easier than messing with a rebuild.

Good luck