Dana 30 gear noise

160 ft-Lb--- Holy Crap! The Dana Light Axle Service manual lists the pinion bearing preload for a D-30 as 15-30 *IN-LB*.

That's the preload, which I have no way of measuring. The 160 fb-lbs is what I tightened the pinion _nut_ to, which is the minimum listed here:

/Peter

Mispoke previously, pls ignore.

From the Dana Light Axle Service Manual: Pinion nut is torqued between 160-500 ft-lb. With the wheels up and straight, check the drive torque on the pinion nut. This should be between 24 and 41 in-lb. (Preload calculated as: 15-30 for the pinion bearing, 3 more for the seal, 6-12 for differential bearing preload).

Peter P> I swapped out the pinion yoke on a late-model Jeep TJ/XJ/ZJ Dana 30 (low

Do you have any end-play on the yoke? If so, you reached your 160 lb-ft nut torque (actually the minimum; 500 lb-ft is max with the collapsible spacer) without meeting your already-collapsed spacer. Incrementally increasing the torque until end-play is eliminated will likely fix it, but keep an eye on the preload as you go. If it gets too tight before you eliminate end-play, you need to start over with a new spacer:

"Torque pinion nut until all end-play is removed and the minimum wrench torque is achieved. Check torque to rotate of pinion with inch-lb (N.m) torque wrench for proper rotating torque. See Specification for proper pinion bearing preload. Continue to tighten in small increments until the proper rotating torque is achieved. Measure the preload torque frequently to avoid overtightening of the pinion nut. CAUTION: IF PRELOAD TORQUE IS EXCEEDED, A NEW COLLAPSIBLE SPACER MUST BE INSTALLED AND THE TORQUE SEQUENCE REPEATED."

Steve

Peter P> I swapped out the pinion yoke on a late-model Jeep TJ/XJ/ZJ Dana 30 (low

Okay, you're describing what I assumed to be the situation.

How am I to measure the preload, I don't have the fancy tool shown in the shop manual? I just have a regular in-lbs torque wrench - can I repeatedly lower the setting on that until I reach one that doesn't "click"?

/Peter

Or set it to the around the middle of the spec ( say 30-32 in-lb) and tighten the pinion until it clicks.

A dial type torque wrench would be better for this sort of thing.

Earle

I use one like this:

A dial type torque wrench would be better for this sort of thing. >

The pinion nut is some sort of stover nut, but it's been re-used a couple of times. Should I be putting some sort of Loc-Tite on it? Red or Blue?

/Peter

Hmm. I think I'll remove the nut and use some blue Loc-Tite then.

All I did on the weekend was install the yoke and tighten the nut to 160 lbs-ft. Just now I removed the drive shaft again and turned the pinion with my lbs-in torque wrench set to 30 with no clicks, so it needs to be tighter. I think there's even a bit of play in it, but its hard to tell what's lash and what play. Unfortunately now I have to wait for a helper with stronger legs than my six-year-old - he can't push on the brake pedal hard enough to stop the wheels from spinning when I turn the pinion nut.

/Peter

Without axles? Sheesh, then it's really too loose since it's taking less than thirty to spin the whole shebang, wheels and tires included.

/Peter

Wait a sec, with the axles out I've no way to stop the pinion gear from turning while I tighten the nut - I'm using the brakes for that. This is a ZJ with a CV yoke thats perfectly round, no flat spots for a wrench of any sort. Naturally, I don't have the fancy tool in the FSM for holding the yoke.

Surely I can't be expected to remove the brake calipers, hubs, and axle shafts to measure pinion preload, then put them all back on to tighten the nut, then do it over again a bunch of times until it's right?

/Peter

The 30-in-lb is *Not* without axles. Steve gave you a link to the Dana Light Axle Service Manual, (

) which is what I also used when I said to go between 24 and 45. Page 9 of the manual gives the specs, and Page 10 gives an example of how to calculate it. So you start off with between 15-30 for the pinion bearing, add 3 more for the seal, and then 6-12 for differential bearing preload (This last number is good for all ratios between 3.07 and 4.88). BTW, the Haynes manual (if you trust it) says you do not have to replace the crush sleeve, instead go for a couple in-pounds more preload which suggests going toward the high side of the spec.

Unfortunately Peter, that is the only way to get it right if you don't have that grabber tool. I would fast be making a bar of steel up with a couple holes drilled into it so I could bolt it to the pinion to hold it steady while tightening.

They are a real bitch to set up and for all the engine and other kinds of work I do, I send out the diffs. Then a Jeep shop did mine wrong even and it cost me a cool $500.00 to fix at a 'real' machine shop!

They are something like setting up a steering box, you cannot do the preload with the steering wheel or drag link attached. If you do, you fast have a dead box.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Peter P>

No, the manual does not account for axle bearing resistance, so axles should be removed when measuring against the calculated spec.

Steve

jeff wrote:

And if you get it right, then you best be running out to buy a lottery ticket because it is your day!

Those preloads are for a R+R job with all new parts. They will not match up to real life on used equipment.

Just my $0.02,

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

jeff wrote: