First off let me say I'm new to these forums. I've been reading them for about 6 months now and today I decided it was time to take the plunge and register. That being said, I'm pretty new to the whole scene and I am mechanically inclined but with very little real world experience. So I have a 1996 T-100 SR5, with about 300k miles on it. I was just under it this afternoon looking at the rubber bushings (they are getting pretty crunch) and I noticed that my CV boot has a minor leak. It seems to be dripping a bit of grease. Now I know that I will most likely need to have the whole joint replaced as that's the best way of doing things from what I've read my question is how necessary is it to get it replaced immediately. Can I drive on it for say 500 miles with a small grease leak before I have to worry or will it ruin something else up in there when the dirt gets in. I just want to hear some opinions on the situation thanks.

tl;dr CV boot is leaking, should I change it immediately or can it go 500 miles.

 

Yes, you can drive if for a while without issue. That being said, if you are doing a lot of off-roading, you could really compromise the joint and it could fail. But just regular street driving will be fine.

Both boots on my T were half-missing, not just cracked, on the wheel side of each CV when i got it. I put at least 1000 miles on it before I had the CVs replaced (street driving).

 

This is gonna make me sound really bad, but I installed my ball joint spacers at 130000 miles. At my next oil change, I noticed that both of my outter boots on my cv axles were seeping grease out from under the inner boot clamp. Now, here's the bad part. My trucks now at 163000 lol. Basically, what I tell my customers, is that yes, it is not good that their leaking grease. But honestly, until they start making clicking noises, or the boots them selves tear, you should be fine.

 

Yea you're just fine. I had both of my boots totally cracked in half for more than a year. Everything will work just fine, but your CV joints will slowly loose lubrication and wear faster. When they are on their last leg they will start to make nasty clicking noises and you will know that it is time. If they do break it isn't a big deal. They won't break anything else and you will have to replace that half shaft (but that's the same situation you have right now). The only consequence of it breaking is that obviously you would have no 4WD until you fix it. The bad news is that the half shafts are kind of a pain to replace, you have to take apart the hub and knock loose the bolts that hold the axle on. Definitely doable In your driveway (I did it), but its an intimidating job if you haven't taken your front drivetrain apart before. I had a hard time tracking down parts when I did mine, there are a lot of seals and small hardware associated with the hub/steering knuckle assembly. You will also want a very good diagram of the hub assembly, as stated there is a LOT of small hardware in there and you need to make sure you put everything back on in just the right order.