I am setting up a new set of Richmond 3.73's in a Moser 12 bolt for my Z.I have pinion depth set to spec as per Richmond specs on gear with T&D pinion depth setting tool at 2.828 with .059" shim stack to get there.Backlash is set at .007" with Richmond setting dimension of .008".I have pics of Caost and Drive side..they look pretty damn close as far as all the gear setup manuals I have from Yukon,Richmond,West Coast Diffs,etc.Just looking for confirmation if these look good or not.HELP!!!!!!!Drive side pic attached..

 

..and coast side pic?

 

It looks Ok for an unloaded pattern. If you can put the brakes back on and pull the e-brake until it gets somewhat hard to turn the pinion flange, that will give a more accurate pattern.

 

You have to hold friction on the ring gear with one hand nice and tight while you rotate the pinion with the other hand to see the impression. What you have there is blank paper with no writing '')

 

I agree...

It looks very similar to the impressions I got when I had too light of a load. With more load: the drive side pattern will widen and move towards the heel, the cost side will make a better impression.

To make my load higher w/o brakes installed. I installed w/o tightening the axle. Then put a tire on the wheel flange and had a friend hold resistance on the tire as I turned the yoke with a ratchet. Also, if you go around more turns the impression become a little clearer.

 

I was having my brother in law hold the carrier as tight as he could while I turned the yoke..but only by hand and that is the resulting pattern.I will try that axle/tire trick to get a better pattern reading..thanks for the info guys.Will report back with the results.

 

So I loaded the gears by installing the axle and bolting a rim on it.My brother in law held on to the rim as tight as he could while I turned the pinion yoke with a 1.5' breaker bar and the pattern became much more pronounced than what is in the pics above..the pattern was larger/longer..this was with the .059" shim stack to get there..specs above in top post.Backlash was set at .007" with Richmond setting dimension of .008".I wasn't all that happy with what I saw..the pattern looked a little too deep in the root of the gear.Then I swapped in a .035 pinion shim stack and set backlash to .010" (again Richmond spec is .008") and rotated the gears loaded like above 5 times both ways with the resulting patterns.By comparing to all the manuals I have handy to me it looks like the pinion is a little too shallow now?The drive side is a little more centered from heel too toe which I like but the coast pattern moved a little more towards the toe (inside) side of the ring gear which I didn't like.It was much more centered with the .059" shims.it is almost like the patterns switched position fom heel to toe when I swapped the pinions shims from the .059" to .035".What do you guys think now??This is the coast side...

 

..and the drive side...

 

Looks a little shallow on the pinion depth for street use and will likely whine a little if you leave it like that. There are two fixes one easy... one not so easy. If you still have some room to increase the backlash within the spec then do so until the pattern is more centered on the gear. If that is not an option becasue you are at the limits of backlash ( .08 seems tight for a limit usually like 0.12-0.14 max but follow the recomended spec here ) now then you will need to re shim the pinion to bring it out a little more towards the ring gear. You are close and could run it without failure concerns but it may be a tad noisy. You are better to have the pattern a little towards the toe than the heal though as you have. Some race only set ups are very much like what you have there with a havy toe favoured pattern but noise is not an issue to them. Hope this helps

 

Thank you very much for that info..exactly what I was looking for.Backlash I actually plan to tighten up to the recommended .008" so that is out.I plan on setting up the pinion with a little bigger shim to move it just a little deeper in the pattern..but not as deep as it was with the .059" shim stack.Somewhere between the .035 it is at right now..but less than the .059" it was at in the first pics.I thought it was a lil shallow for street use.Mainly a street car with occasional track passes.Thanks alot man..will post back again.

 

Anyone else?I am going to swap in a .047" pinion shim stack and see what I come out with.That is about halfway between the two settings I have tried out to date?

 

Well, I wasn't going to say anything because it seems like you have it under control but....

I think your closer now than where you were. I'd lean more towards the smaller shim. On the other hand your only planning to move it .012. I'm thinking slightly less.

Try to interpolate a value based on your before and after pictures. A shim of .047 should put it right in the middle. Is that where you want to be or do you want to be a little further out?

From what I can see you want to be a little further out than the middle of the new and old settings. How much? I'm not sure. You had the best view of this. Do you agree with what I'm saying though? Maybe from your view right in the middle is what you think is right. If so, then go for it.

BTW: How are you replacing the shim? Are you getting the bearing pressed on/off or do you have a slip on bearing?

It seems like your a weekend warrior like me.

Good Luck!

 

Agreed. Better a little toe favoured than too far out on the heal.

 

Thanks for the reply.I agree with what you guys are saying.I always second guess myself and that is the reason I posted..always prefer a mojority vote..lol.I was going to add .012" to the shims but like you and 87roc_t56 stated I think I will only add about half of that to keep it on the shallow side as opposed to going too deep again..maybe only add .006" or so.I have both brand new pinion bearings honed out for set up with a brand new set waiting for final assembly..only way to build a rear.Yeah a weekend warrior..actually only a saturday warrior.6 day work week..new house..fiancee..and two kids...leaves very little time to try and get this rear finished. Will post back this weekend with new pattern..thanks guys.Almost done!!

 

OK..take three.These pics are a .040" shim stack on the pinion (.005" more than above pics),correct preload on pinion bearings and Richmond recommended .008" BL.I think the pattern is good?!I am pretty happy that both coast and drive favor the toe a little more.What does everyone think??I hate this two hour allowance I have each week to build this thing..I can't wait to finish up.This is drive side...

 

...and coast side...

 

Nice work. Patience pays off eh? Just remember to break the gears in before you hammer it!

 

Thank you.Patience is not one of my better traits either..but hell yeah it pays off!So you think all is well?I was actually considering setting it up one more time with a little more pinion shim..that was a .040" in those pics..I was considering a .042" to .044" but on the other hand I like what I see there and don't really think .002"-.004" is gonna change the pattern enough to notice?!?!Do you think there is anything to gain by opening up the BL to .010" from the .008" it is at right now (Richmond recommended & engraved on the ring gear)?I am just weary that is I set it up at .010" it will clunk when I let the clutch out.Plus I am tired of setting it up and tearing it down so many damn times..lol.Now I am in the process of setting up the Ratech solid pinion spacer.It previously has a crush sleeve which I refuse to run in any of my rears anymore.I seriously think that is more difficult than setting up gear pattern..and this is the fifth one I have set up It gets no easier even after you learn the first one.I am starting to see light at the end of this tunnel!!!:lala:I am open to any and all suggestions from the pros???

 

Yea thats close there. I would stick with your plan and add a .004 shim. That will put you spot on or very close. Richmonds whine even installed to thier specs, thier pattern no matter what. Thats why I would use them in customers cars.

 

Any other suggestions?I am open to everything at this point.I am trying to finish this thing up this saturday!Please...I am going to go ahead and add .004" one final time to try and get a "perfect" pattern..or as close as I possibly can..

 

TTT..any other suggestions...comments...anything?I will post back monday when I get a chance to add the .004" and see what the pattern looks like.

 

The backlash spec still sounds a little tight to me so i would set it at the maximum recomended allowance as this will allow more lubrication and the gears should run a little cooler and hopefully last longer.

 

That sounds good..I was thinking of opening up the backlash anyway.Like I stated before Richmond recommends and even stamped it at .008" on the ring gear.They state that maximum allowance is + or -.004" either way..their range is .004" to .012".I am thinking of setting it a .010"? .012" just seems way too loose to me (again..to me)..I am afraid of the shock when I launch (usually like 4500 and up) with the manual trans that the clearance of .012" would cause the gears to really shock when they finally mesh...maybe I am just over analyzing it also.Keep 'em coming..I am hoping to finish up all final set up specs this monday and actually finally assemble it next saturday after a thorough cleaning of all parts.

 

I misunderstood ealier it seemed to me as though .008" was the maximum allowable spec but now I see it is more familiar with the .012" max. Setting it at .010 would be fine but I would shy away from anything tighter than .008"

 

Sorry if I confused you in the way I posted the specs.Thank you very much for your help in this project..greatly appreciated and helped greatly.That goes to all the others that posted also..I owe you all a beer or two..I know I will enjoy a fair share of my own when I finish this puppy up.Happy 4th guys!

 

To me the depth, on the drive side pics, look to be below the center already. (I seem to be in the minority though.) I'm not sure I would want to add more shim on the pinion. Anyhow you could try it and see how it looks.

For the backlash, I'd shoot for what the ring gear says and balance in all other factors. It looks like your at .008 now, the gears say .010. Your pattern is on the toe side. So, I don't think it will hurt to increase your backlash to at least what the gear maker says.

 

Correct..it is at .008 now..I want to increase it to .010.What do you mean by "the gears say .010"?The maker states + or - .004" from their recommended setting of .008". I figure shoot for the middle of .008" recommended and max of .012" putting them at .010".This should move the pattern a little more towards the heel correct?In effect centering it more on the gear?I am jut praying the gears last and don't wine..but being Richmonds hopefully they'll whine only slightly

 

The pattern will move out towards the heal the more you increase the backlash.

 

Sorry, Onebad82Z.... I mis-read above. You did say .008" was the gear recommended backlash and not .010".

I agree with you, I don't like the idea of it being too loose. On the other hand, your marks are on the toe side. Not terrible, some might even prefer it for a "competition" setting. It might be more noisy there though.

Just FYI: When you are measuring the backlash with your indicator, be sure not to clunk the ends. I found that if I clunked the ends my measurements were off. Try turning the ring gear very slowly until it presses against the stops and see if it makes a difference.

Best of luck to you!!

 

Alright guys..heading over to work on the rear and try and finish it up today.I am going to leave the pinion depth where it is at and increase backlash to .010".The majority seems to be leave it (pinion depth) where it is and increase backlash from you guys here and a few other friends I had take a peek at the gear pattern..so the majority wins.Now if I could just get that damn Ratech pinion spacer set today..I would be in business.:lala:

 

A little too much backlash is better than not enough.... up to a point, it doesn't hurt anything; and since gears grow when they get hot, then if there's too little, they'll bottom out and bind on long highway driving and hard use, if it's set too low during assembly.

.010" is fine, I'd say anything in the range from .006" up to .012" is OK. I usually set it to .008".

 

One last try here guys...I set it up with a .042" pinion shim (from the previous pics of .040") and it just looked to deep..so I went the opposite way.I set it up with a .038" shim and increased backlash to .0095".I like the pattern alot more...it is only a small move in pattern but it is more centered especially since I opened up the BL.Just for the hell of it I set backlash at .013" and the pattern was damn near centered..but that is way too much.No matter what pinion shim I set it up with the pattern always favors the toe side...which is always the favorable side.Coast side..

 

Drive side..

 

Ooh Smithers... thats EXCELLENT oohhh

 

So??? How is it working????

 

lol..man I wish I could tell ya.I am now in the final process of this build (which will happen next saturday now of course..a weekend warrior ya know)....setting up the Ratech solid pinion spacer.I narrowed it down to which shims are needed and I have to sand the actual spacer itself mere thousandths of an inch to gain about around 3-4 in-lbs to get to the correct rotating torque for the new pinion bearings.Even a .001" shim removed makes it too tight..rrrr.Rest assured as soon as I get her installed and drive it...you guys will be the first to know.Thank you very much for all the help guys..greatly appreciated!Learned alot I thought I already knew..know I actually do.Couldn't have done it without all your help...a beer on me for all!

 

So it's been almost a year since I finished building this thing and it's finally IN!!!!!!

Here are my results!!!

Only an initial 10 mile break in cruise..but up to about 35mph it is dead silent.After that it whines...actually it's more of a howl on decelleration and at light cruise at anything over 40mph or so...didn't go much over 50mph as I didn't want to overheat the gears on the initial break in cruise.According to Richmond I have to do this 2 more times..10 miles and let it cool over night.The howl is not bad by any means...slightly louder than the Holley black electric pump.Finally found something to drown that damn pump out...LOL.As I was cruising I would slowly roll into it (throttle) and roll back out to load both sides of the gears..under any more throttle than a light cruise (under medium to heavy load) it is dead silent..only howls at light cruise or decel.So that makes me think the pattern is about where it needs to be as Richmonds whine no matter what.Two more breaks in this weekend and a few more things on my list of "to do's" and I am heading to Englishtown June 11th for the Camaro/Firecird vs Mustang challenge

 

I had a set of Richmond 3:73's installed in mine, and they whined about like yours do at first, then they got to a point after putting around 150 miles on them, where they just whined a little bit at the sweet spot while cruising (maintaining given speed usually above 45mph). If I decelerate, they are almost quiet, and the same for accelerating, pretty quiet.

So I drained the gear lube and filled it back up with an industrial synthetic 140W gear lube from BP. I havent had it out yet since I switched to the synthetic.

We'll see.

 

Well..after putting around 70 miles or so on the car before my fuel pump ****, the rear is doing well.It still howls on decel and on light cruise...but the howl has gotten much quieter than the initial drive.And the part I am happiest about is the gears are dead silent at my usual cruise mph of around 55-60 or under any heavy throttle.Not a peep out of them!!I should have the new fuel pump by monday so then I will resume continuing to put some more break in miles on them before the E town event...and hope they quiet down some more even.But even so,they can't be that loud as my 7 year old step-son fell asleep in the back seat on the last 25 mile cruise I took it out for.I plan to add some more miles,hit the E town event,take it to my wedding on the 17th and then the following week change the gear oil to some Redline shockproof.Right now I am running the Richmond synthetic gear lube that came with the gear install kit.