Mark Gildersleeve

I've got an issue. 05 v6 5spd 373 gears. Just got done replacing the pinion seal in the rear end (7.5). And after doing so have a very low rumble in speeds above 35 or so when the driveline is in between pulling and slowing the car down. Here's the whole story:

In this procedure I removed the brake disks, calipers, rear drive shaft connection to the rear yoke and yoke connection to the pinion shaft (which by the way is a 27mm bolt). I put the whole thing back together making sure that the pinion/yoke bolt was generally the same tightness as it was when I removed it. (there's that whole dance about the amount of force it takes to turn the pinion shaft with no drag on the axles - hence the need to remove the brakes) I hope this is not where my problem is...

So, I drove it down the street and everything is fine up to about 35mph. above that there is a very deep low vibration that only happens when the driveline is slack - in between speeding up or slowing the car down. So in that mid-ground between the two there is that strange rumbling, almost sounds like a really low subwoofer type sound. So the question is: What did I screw up? I put the yoke and the driveshaft back together in the same orientation that it came apart. I did notice that the e-brake handle has a lot more travel than it did to start with... could that be it? Any input would be appreciated.

tx_zstang

Ok I can offer some suggestions.

My first initial thought when reading the thread title was maybe the draveshaft wasnt put back on properly, flush with the pinion flange or something. I dont think that's your issue.
It sounds like you dont have the pinion nut at the right torque.
Putting it back on, you really need to measure the pinion pre-load using an INCH-POUNDS torque wrench, not a large typical ft.lbs one. Actually, you needed to do that before removing the pinion nut to see what it was at; and you could have done that with the brakes and all still on, since it was just a flange removal/install.
Ok well, now that you didnt do that, all is not lost. You still need to get the pinion nut to the right tightness. Using the tighten until it hits the crush sleeve method is very rough and may work but not one I'd recommend.

By not having the pinion nut at the proper torque, you risk damage to the pinion gears, as well as improper pinion depth and backlash alignments. Being close, it will work, but will make noise.

It sounds like you are hearing 'growling' and not 'whining', which is indicative of pinion bearing/depth issues.

So how do you fit it? First, get ahold of a inch-points dial-type torque wrench. You may have to order one or borrow one (I bought a kd-tools one from amazon.com for $35 or something; 1/4" drive). You'll need to unhook the driveshaft at the pinion flange, raise the wheels, and remove the wheels to reduce the weight on the driveline. You dont have to remove the axles from the differential, but probably should for proper measurment (although others may comment on this). Then using your inch-pounds torque wrench, turn the pinion nut clockwise (I think) and see how much torque is needed to keep it moving; iniitally to get the pinion turning will take more force, so get it turning and then see how many inch-lbs it takes to keep it turning. I thin spec for used bearings is 8-11 inch-pounds. If you're at more than that, the pinion nut is overtightenned; if you're less, then it needs to be tightenned some more.

If you've overtightenned, like I did one time and measured foot-pounds instead of inch-pounds (!), then you need to replace the crush sleeve (remove the pinion flange and seal, pop out the outer pinion bearing, and pull out the crush sleeve, then put it all back together); tighten the pinion so it's all the way down and the crush sleeve starts to crush, checking the 'preload' usning the inch-pound torque wrench.

Oh yeah, put red loctite on the pinion nut!!! If you dont, IT CAN COME LOOSE!!! That too could be your current problem!!!

(Don't feel bad; I did a similar thing the first time I did rear end work. Eventually we fixed it all, but yeah, getting the pinion torqued properly is a very important step in these rear ends.)

svastano

I agree with above it sounds like you tightened the nut too tight and destroyed the crush sleeve. This will ruin you ring & pinion in a hurry if not corrected.

Mark Gildersleeve

Thanks for your input... That's what I was concerned about and I think you're probably right. I actually was unaware of the crush sleeve and know now that I probably did indeed crush that sucker. I did every thing as you described - I checked the amount of torque was needed to turn the pinion. It was necessary (as described in the Hayes manual) to remove the brakes because the little amount of drag they cause makes it hard to measure the torque. If I over-tightened the pinion nut it was only by a little bit but not knowing about that crush sleeve I did tighten it dow a little farther until It got a little tighter then backed it off a bit. I'm guessing that if this is indeed the issue I must have over-tightened it just enough to damage the sleeve.

I'm still holding out hope that I did something dumb (and easier to fix) like not getting the drive shaft put back properly... but with my luck I'm going to have to tear it back down again. Crap.

Good point about the Locktite. I was wondering what kept that thing from backing out...

How EZ is the crush sleeve to pull out? does it just slide in? What's that thing do anyways?

Thanks!

Mark Gildersleeve

Here's another dumb question - how do I post a pic like you guys have at the bottom of the message? Sorry to be such a D.A.

tx_zstang

Your "signature" in your user profile is where you can add in pics.

The crush sleeve is not easy to get to, but not really too bad. And you can buy a package of them at your local auto store for like $5 I think, so you dont need to go to the dealer for one.
It serves as a wide hard spacer between the outer pinion bearing and a portion of the pinion shaft for proper torque on the pinion bearings. It "crushes" or gives so when the pinion nut is tightenned, the proper pressure can be applied and and adjusted for the pinion bearings.


To get to the crush sleve, disconnect the driveshaft, remove the pinion nut, remove the pinion flange (using a puller), remove the pinion seal (probably will want to get a new one), and then, simply using your fingiers, carefully pull out the oil slinger (thin ring) and pinion bearing (both will come right out easily). The crush sleve will be the next thing on the pinion shaft; it's round and kind of reminds me of a typical wedding ring in its shape. Just slide it off the pinion and put a new one on, then reverse order everything: pinion bearing, oil slinger, pinion seal, flange, nut (w/loctite), torquing to specs for proper pre-load (make sure the pinion does not have any slack moving in/out); the pinion flange should be quite a bit of ways on there but minght not quite be all the way down before you encounter the very tough crush sleeve. Gradually tighten, getting pre-load right!!! Once it's set right you should be good to go. I haven't used the haynes manual, so hopefully it describes what I'm talking about in detail.
*** The preload spec is critical. *** get it right! (remember, INCH-Pounds, not foot-pounds)

You probably don't have to pull the cover to do this, but the proper complete way would be to pull the cover and after installing the pinion parts to proper torque, re-check the backlash and adjust if needed. If you get the pinion pre-load torque right, your backlash will probably still be ok and not need adjusting.

Doing it right takes a little practice. An alternative is to have a reputable shop do it for you, too.

157dB

http://iihs.net/fsm/?dir=87

andresspeedygonzalez

Did replacing the crush sleeve and checking and tightening the pinion nut to 8-11 inch pounds fix the problem?
I had a mechanic replace the pinion seal and I have this exact same vibration / growling problem. It's been 3 months trying to find a fix. I am desperate. Any reply confirming if the issue is fixed is GREATLY appreciated!

imp

Crush sleeve blues! If the big nut were tightened enough with NO CRUSH SLEEVE, the bearings would be OVERLOADED and ruined. It takes several thousand pounds of force, applied by the tightening of the nut against the crush sleeve to bring the two bearings together with an appropriate amount of PRELOAD on them. That requires lots of torque applied to the nut, >100 ft.lbs., assuring the nut stays tight and the bearing preload cannot change. It is always advisable to REPLACE a used crush sleeve with a new one; a used sleeve may NOT take much force to preload the bearings, the nut will then be too loose, and may back off, ruining the bearings.