took out differential for grinding, whining noise

[golfprowanabe]

I took the diff out and have the front cover off of it. Is there an auto store or something that I can go and buy a dial indicator? I think it might have too much play. Also, what else should I do to it while it's out. Is it a good idea to replace all the bearings and such or is this not an issue? I'm just tired of hearing the grinding sound ( i guess this is the howling or whining sound I hear others talk about), which ford has said it's definately coming from the diff. They want $250 for them to open it up and look at it so I did it myself. All your comments will be appreciated.

thanks,
David

 

[midwestcobra03]

how did you get that cover off? I just had my diff cover crack. Do you have to drop the whole rear? How long does it take?

 

[golfprowanabe]

I dropped the whole rear. There is only like a half inch of clearance otherwise. I don't see how you could take it off without dropping it.

 

[golfprowanabe]

Ok guys and gals... I bought a dial indicator and base at NAPA and did the measurement. It was .032 Would you all say this is wayyyy out of tolerance, or it is to be expected? Is this a good probability of the grinding, whining sound I get? Should I just shim it properly, or is there other things I need to do? I could really use some good help!
thanks

 

[RKANYZ]

spec is .008-.012.

how do the bearings feel? does the pinion flange rotate smoothly? it should rotate smoothly but have no slack or play in it. how do the teeth look?

 

[ShelbyGuy]

take it to someone with the tools to set up a ring&pinion. you didnt even have a dial indicator. that means you're not going to have a case spreader or companion flange holder. do you have a dial-type torque wrench to take a preload reading off the pinion nut? how about gear marking compound so you can read your pattern?

 

[golfprowanabe]

ShelbyGuy,
I'm rather mechanically inclined, although I've never taken apart the diff before. (I have totally dissassembled and reassembled my tranny!) I'm slowly building up my garage as needed. I'll go buy a case spreader and flange holder if needed. Yes I do have a dial-type torque wrench. I know alot of rebuild kits come with pattern marker and a brush. My question really is... should I totally rebuild it while it's apart, or is this most likely wasted money and I should just reshim to move the ring gear closer to the pinion gear? Would you say that seeing .032 movement in the ring gear is common, or is this unusually out of tolerance?
And with whatever it is you think I should do, where is a good place you'd recommend getting what kit?

take it to someone with the tools to set up a ring&pinion. you didnt even have a dial indicator. that means you're not going to have a case spreader or companion flange holder. do you have a dial-type torque wrench to take a preload reading off the pinion nut? how about gear marking compound so you can read your pattern?

 

[GtownMACH]

32 thousandths is too much.. yes. Around .010 is ideal.

 

[golfprowanabe]

anyone have a good idea on what kit to buy and where to get it?

 

[Charles236]

If you have to buy a case spreader, the cost of it alone will be more than most shops charge to install gears. I have seen people hammer the shims in on an aluminum case, and it is a surefire way to damage the aluminum case. If you do decide to do the work yourself, it would be worthwhile to get someone who has experience in setting up rearends to coach you through it.

 

[ShelbyGuy]

and the case spreader does not come with the adapter plates to mate the spreader to the housing. the spreader is available through several otc/spx dealers (i think i got mine through toolsource.com or tooltopia.com) and the plates can often be found with other tools in Rotunda service kits.

you would at least need:
case spreader and adapter plates
wiggle bar for the dial indicator so you can see how far you've spread the case (.030 is spec)
bench fixture to hold above mentioned items, as well as the diff housing they'd be attached to
companion flange holder - you can make your own. big piece of steel with holes in it to bolt to the companion flange
pinion depth tool
pinion bearing install tool (or old pinion bearing that you've ground out the inner diameter so its a slip fit instead of a press fit)
dial-type torque wrench to measure pinion bearing preload
bearing splitter to get the pinion bearing off.

Max ring gear backface runout - .003"
Max diff carrier case runout - .003"
Backlash - .008-.013, .010 preferred
Pinion bearing preload - 8-14 lb-in for used bearings, 15-29 lb-in for new bearings
Initial breakaway torque - 20 lb-ft
Pinion shaft lock bolt - 22 lb-ft
Bearing cap bolt - 24 lb-ft

The Ford Racing diff rebuild kits are actually from Ratech, if that helps you get them any cheaper.

 

[golfprowanabe]

Well I think I've found the problem! My carrier bearing and race on the ring gear side was chewed up a bit. The race had some scuff marks and was not really smooth at all. The bearing looked all knicked up as well. The other carrier bearing and race was smooth as silk. I'm assuming this was the actual 'grinding' sound I heard, and not just a howling sound. I do believe I got the howling sound because the backlash was measured at .032.

I'm going to replace both the bearings and reshim so the backlash is set properly. Since I don't have the proper tools and I don't think anything is wrong with anything else in the rear, I'm going to leave the pinion alone and not touch the axle bearings either. Both axle bearings look smooth. I hope this solves my case!

 

[golfprowanabe]

Damn double post!