Propeller shaft re-torque is it needed?

[TechWrench]

TechWrench, I think I understood that part of your earlier post:

"I may not have been clear in my earlier post, but I was refering to the slip joint in the shaft, not the u-joints. I can't imagine anyone attempting to dismantle the u-joints to clean and lubricate them and reinstall them again."

I was talking about the slip joints too--I haven't been able to find any suggestion that they be removed for lubrication purposes, and that seemed to be what you were suggesting.

I still wonder about eventually filling the slip joints since there appears to be no place for the accumulated grease to go. I don't know how the grease passages are arranged, so I can't say whether a few pumps are enough to ensure that the splines actually get lubrication, or whether it takes a greater filling of the joint to drive grease in there. I wish the repair manual was more specific here.

I agree with you about the fact that no amount of lubrication will make the joints last forever, and that in most cases only a modest amount is needed for these driveshafts. As a matter of fact I've posted elsewhere here that I'm surprised at how often Toyota recommends that these shafts be lubed and re-torqued. There must be some specific reason behind that part of the service schedule, but I can't figure out what it is.

Maybe the experiences of others will enlighten us on one or another point here.

Yes, the overhaul procedure is where the slip joint servicing is detailed. And I didn't mean to suggest that everyone should remove their driveshaft to do this. But if someone did put too much grease in the joint, that would, IMHO, be the only way to remove the excess safely.

I think the problem we both are having, if I may be so bold as to assume on your part, is that many of the posts asking for advice on lubrication procedures are looking for a specific detailed procedure on how to do the exactly perfect lubrication so the component in question will last 'forever'. I has been my experience over the years, that there is no one perfect answer when it comes to these type of questions. This is a, IMHO, very subjective area. Is 2 pumps enough, is 5 too many? I am sure that if one went to 5 different shops and asked the mechanics, you would get no two same answers. I think individual experience is the determining factor in each case, and none of them will be all wrong or all right. It is hard to explain to a novice when enough it enough. I am not trying to be too cavalier, but sometimes I think that too much worry is spent on the smallest of issues. I will always prefer to do my own vehicle servicing for many reasons, but still would rather be driving it that lying underneath it.

 

[MicaBlue03]

TechWrench, I see your points more clearly now, and agree that this duscussion can be taken too far. For most people, the best approach is probably to give each of the zerks a couple of shots of grease once in a while, and forget about it otherwise unless problems appear. When the joints eventually wear out, fix them.

In making things more complex than they really need to be, perhaps we are inspired by Toyota's requirement for two different types of grease, along with fairly frequent greasing and torque checks.

 

[Jim_Chow]

Re: Re-torque & greasing

[snip]
For the splined slip joints in the 4Runner there is a cylindrical cover over the joint that (I think) helps retain grease in the joint. The first time I greased this joint it took lots of (more than 20) pumps and I could tell I'd filled it when the shaft/cover just started to try to extend. After that, many fewer pumps were needed. I worry a little about overfilling this joint, as I'm afraid of blowing a seal and/or throwing grease onto the underside of the vehicle and getting it on the hot exhaust. I have yet to see any greae forced out by bumps, etc. since greasing.

As techwrench said, you don't want to overfill the slipyoke w/ grease! If you do, the prop shaft can't contract like it should, so the stress gets tranferred to the t-case/diff. I overfilled it the first time and then read about it (This was discussed in detail on the LC site ih8mud). If you overfill, you can theoretically remove the zerk, drive around the block or up/down speed bumps/curbs to allow excess grease to squeeze out, then replace the zerk. I never retorqued the d-shafts on my '86 runner, and they've yet to loosen after 18 yrs.