Richmond 4.11s backlash?

[steeleshark2]

My installer said they installed the new 4.11s to .010 backlash. They test drove the vehicle and had bad whine. They believe that the backlash was too much. They are going to reset the backlash to .006.008 and believe it will fix the problem. What do you all think about this? Is .006 too small of a backlash? Is it safe for these gears?

[camaro1]

pinion depth is probly wrong,, richmond has a special pattern for these gears that is deeper than a person is used to setting them up. any pics of the pattern after they set them up?

[Russell James]

There is more to it than backlash. Richmond has an installation pdf on their website that explains all the set up steps. The depth and backlash should be engraved on the gears. They give examples of what the pattern should look like on the site.

The backlash will be on the ring gear. You have to get the pattern correct and stay within .004 of the spec number. I'd call Richmond and see if they have any advice on how to tight to be within the spec. But first read the drive and coast pattern, because if it whines bad - the pattern is probably way off.

[steeleshark2]

Originally Posted by Russell James

There is more to it than backlash. Richmond has an installation pdf on their website that explains all the set up steps. The depth and backlash should be engraved on the gears. They give examples of what the pattern should look like on the site.

The backlash will be on the ring gear. You have to get the pattern correct and stay within .004 of the spec number. I'd call Richmond and see if they have any advice on how to tight to be within the spec. But first read the drive and coast pattern, because if it whines bad - the pattern is probably way off.

Thanks, I just wanted a second opinion. It is a GM master mechanic doing these gears at the shop and has done many different types of installs. They set them per the instructions and verified correct. The whine was the result. They said everything was right on. They did just mention the backlash but could be a little more to it then that. I just wanted to see others thoughts and if anyone else went with a smaller backlash then .010.

[Russell James]

I saw another post where Richmond recommended .008 to .010 backlash

So, if you could get it to .008ish and with a perfect pattern, that should be in the ballpark. I also saw some info on they must be installed correctly using a case spreader. So I'd ask that specific question - are you using a case spreader?

If they seem to be doing everything perfectly and it still whines, have them call Richmonds tech support line.

[chvyman]

as posted above, backlash doesn't give whine but possibly a clunk. Pinion depth is the culprit of causing the whine.

[55Designs]

we noticed whine at first but it went away as the teeth broke in. I heard somewhere on here Jannetty sets them tight for that reason. You might want to give him a call he does a ton of these diffs for people on the board.

[GrinderSS]

Originally Posted by steeleshark2

My installer said they installed the new 4.11s to .010 backlash. They test drove the vehicle and had bad whine. They believe that the backlash was too much. They are going to reset the backlash to .006.008 and believe it will fix the problem. What do you all think about this? Is .006 too small of a backlash? Is it safe for these gears?

When I setup my gears I set the BL 0.002" less than was indicated on the ring gear because I had also installed all new bearings and races. Setting it up a little tight with new bearings is common but not required.

[steeleshark2]

Originally Posted by GrinderSS

When I setup my gears I set the BL 0.002" less than was indicated on the ring gear because I had also installed all new bearings and races. Setting it up a little tight with new bearings is common but not required.

Good to know, thanks a lot!!

[MudderFinger]

Richmond did just recently update the clearances after having allot of failures on the Camaro, there are other threads about people having issues tearing up the 4:11 gear sets and most gears are being shipped with a appendex with new specs. I will try to find and post the thread.

[55Designs]

Originally Posted by MudderFinger

Richmond did just recently update the clearances after having allot of failures on the Camaro, there are other threads about people having issues tearing up the 4:11 gear sets and most gears are being shipped with a appendex with new specs. I will try to find and post the thread.

I know alot of 410 blew up and they revised them to the new 411. I have yet to hear from any shop on the 411 breaking. Set up is a bitch thats why we dont even do them in house.

[steeleshark2]

Yeah, haven't heard of many problems with the 4.11s blowing out.

[FiveO]

I have 411 gears on order as well, I hope we dont have that same problem.

[steeleshark2]

Originally Posted by FiveO

I have 411 gears on order as well, I hope we dont have that same problem.

Sorry, forgot to update everyone on what was going on. When I originally made this post, I had information second hand. The actual issue was the crush sleeve was a bit weak and did not do its job. My shop ordered a stock crush sleeve from GM and reinstalled everything. My wife now has 250 easy miles on the car with ZERO gear noise. Gonna have her to continue to put more easy miles on it while I am deployed and then get the gear oil changed. It will be ready for me to have some fun when I get home early June!!