pinion bearings, i searched, but my question was not awnsered.

so, i have never tore apart a differential. my pinion is very loose.

could i replace this bearing and use the stock shims and probably be okay?

i understand the new bearing needs to be pressed on, probably by a shop.

could i go to the junkyard, pull a pinion with the pressed bearing out of a good tight differential dana 30, install that in my dana, and it work out properly?

dailydriven, 4.5 rough country. 87 pioneer.

mscans said:

so, i have never tore apart a differential. my pinion is very loose.

could i replace this bearing and use the stock shims and probably be okay?

i understand the new bearing needs to be pressed on, probably by a shop.

could i go to the junkyard, pull a pinion with the pressed bearing out of a good tight differential dana 30, install that in my dana, and it work out properly?

dailydriven, 4.5 rough country. 87 pioneer.

Click to expand...

No. There's this little spec called "preload" that is critical.

The shims are there to set pinion depth and therefore pinion gear-to-ring gear engagement - IIRC, reusing them isn't such a problem. However, you have to have an inch-pound dial torque wrench in order to properly set the preload on the bearing - set it outside of a fairly small range, and you'll wreck it in rather short order (thinking on the order of minutes, here...)

It is possible that you may have to alter the shim pack due to tolerances in manufacture (for instance, if the new bearing is signficantly thinner or thicker than the old one - somewhere around .002-.003" off...) but it's not likely, they've gotten quite good at this sort of thing.

You may want to post up in your local chapter to see if anyone near you has experience in axle work, and has the tools. That would save you shop rates, and you'd learn something in the process (which can help you later.)

Good luck!

mscans said:

could i go to the junkyard, pull a pinion with the pressed bearing out of a good tight differential dana 30, install that in my dana, and it work out properly?

Click to expand...

No
1) the gears are a matched set. You.d have to pull and swap both the ring and pinion gears.
2) The shim set matches the pinion to it's bearing set and the individual case. Change any component(pinion gear, bearing, swap between axles) and you at least have to check pinion depth and pre-load. Unless you are very lucky, it will need at least a minor shim adjustment.

mscans said:

so, i have never tore apart a differential.

Click to expand...

Find someone who knows how. There are a couple of specialized tools needed to set up gears. It's not hard if you have the tools.

The pinion and the case have the biggest influance on the shims needed to set the pinion depth. Since you are going to keep both of those, using the shim that was there will give you an acceptable pattern 95% of the time. The HP30 also uses shims to set the preload, so you may have to play with these shims to get it right. Now before you go ripping everything apart, is your pinion nut tight? It may have just loosened causing the play that you see.

Durango-Bob said:

The pinion and the case have the biggest influance on the shims needed to set the pinion depth. Since you are going to keep both of those, using the shim that was there will give you an acceptable pattern 95% of the time. The HP30 also uses shims to set the preload, so you may have to play with these shims to get it right. Now before you go ripping everything apart, is your pinion nut tight? It may have just loosened causing the play that you see.

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i will try this tomorrow, i doubt it's the problem, but i will hope like hell it is.

a guy in my jeep club knows how to do this stuff, so i'll hook up with him.

thanks everyone for the awnsers to my question though.

one more question, if i pull out the pinion, and leave in the carrier, and tape the hole shut, can i drive my truck safely like that? moderately safely?

hey mike it shouldnt be that hard to replace that one weekend. my pinion bearing went out on my front end so i just got another one, was more cost effective but i know you just replaced all those ball joints. we could set up somewhere and im sure me you and jay could pull it off. i have torque wrench for setting along with the proper socket and i also got a dial indicator for gear mesh settings. let me know.

mscans said:

one more question, if i pull out the pinion, and leave in the carrier, and tape the hole shut, can i drive my truck safely like that? moderately safely?

Click to expand...

You can pull the pinion and drive like that(also removing the drive shaft), but to remove the pinion, you have to remove the dif. carrier, which means you have to pull the axles, which means you have to pull the wheels, brake calipers, and unit bearings. Unless something in there is broken, just don't put it in 4WD and it'll be fine.