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Discussion Starter · #1 ·
I helped a friend install some 3.73's in his 95 mustang gt. He had 2.73's. Once done, he said there was a whine under decel only.

I set the pinion preload, used the stock .030 shim. Torqued the nut down slowly till i got to 140 ft lbs (minimum to start crushing the sleeve), then check my preload, it was 15-25 in lbs. That is what the 8.8 calls for. Also made sure the pinion depth was the same at the old gear, it was. Installed the carrier, had .012 backlash. I thought the runout looked good, but i only had a painting marker and a little grease to check it with. Any ideas?
 

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Generally, when gears are noisey on decel, the pinion is too deep. Ya need to get some white grease and check the pattern closer. Wipe off the oil and paint the pinion only and see what it leaves on the ring....
 

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Preload is not your problem, the problem is your pattern is probably off. What we normally use to check a pattern is titanium dioxide and not white grease. You can get a small tube of it from your local Ford dealer.

Side note: Some gears sets will remain a little noisy even when everything is set properly. As you go up in numbered gear sets they tend to get a little more noisy. I had a 3:70 Ford Racing gear set in my Currie rear axle in my 34..set up by Currie and it was noisy. I pulled the third member and checked the pattern, it was right on. I was running low profile tires and the highway RPM was a little higher than I wanted with the 3:70 so I replaced it with a 3:50 and it is very quite. Just because it's a Ford Racing gear set does not mean it won't be noisy if set up properly. Ford contracts out the manufacture of gear sets.

Vince
 

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When you say run-out I assume your talking about the ring gear run-out. If that is the case you need to determine what is causing the run-out. More than likely it is the carrier assembly where the ring gear mounts to it. The surface is uneven which does not allow the ring gear to bolt down square on the carrier, causing the ring gear to have high spots. No amount of adjusting carrier bearing shims will fix this.

Vince
 

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If I understand your original post, sounds like you set the pinion gear only by the depth measurement? If so, it is likely too deep or too shallow. Whine in deceleration is gears too deep typically. I know pros who ONLY rely on the grease reading on tooth pattern, raw depth readings aren't very reliable. get a tube of gear setting grease and do it that way. If you don't have one, get a cheapie Harbor freight dial indicator (plenty accurate for 99% of what you need to do), and set the gear lash to spec. You already have the bearing pre-load figured out so if you do those other two things, you will have the gears as good as they can get.
 

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Starting with the old pinion shim is a good idea, but most of the time,some changes will need to be made for a correct pattern. You might double check the pattern.If your having a hard time reading the pattern you can pick up some purssian blue part# 80038 or if you have some of the white thread sealer,those show the pattern really well.

Look at the coast side pattern and see if it's running real HIGH or real LOW on the tooth.

If the pinion depth is incorrect and the coast side is high,the drive side will be low.

If the coast side is low the drive side will be high.

In both cases you will need to do a depth change. This might help you in case you need to do any changes.http://www.ringpinion.com/Content/H...tions/Yukon_Installation_Kit_Instructions.pdf
 

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Discussion Starter · #16 ·
Yeah. Honestly it wont be that bad. After seeing what all needs to be done, it wont take long at all to get back off. Although getting the bearing off the pinion can be a PAIN. The outer race can be really flimsy and want to separate from the bearing. The pulling wont grab the inner race because it tight against the .030 shim. To tight.
 

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Rubberman2003 said:
Thanks all, sucks ive got to pull it back out to reset it. Can i save my fluid i put in and reuse it?
Yes you can save the oil as long as it's still good and clean. It does suck,but it happens to the best of us!

I doubt it's a run out problem,but just check your backlash in different places. If there is a runout problem,the backlash will not be consistent.
 

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Rubberman2003 said:
Yeah. Honestly it wont be that bad. After seeing what all needs to be done, it wont take long at all to get back off. Although getting the bearing off the pinion can be a PAIN. The outer race can be really flimsy and want to separate from the bearing. The pulling wont grab the inner race because it tight against the .030 shim. To tight.
Don't use a bearing puller on those bearings! As you mentioned, the roller retainer isn't up to the task and damage to that will absolutely result in a quickly failed bearing (don't ask how I know - I been thru several learnin' sessions in my career!). Use a bearing remover on your press line this HFT one.




Great for wheel bearing pulling too. I cheaped out on this tool by making my own from a piece of heavy 4" angle iron. I cut a notch in one of the flanges that the shaft/axle slips into then ground the edges so it fits under the bearings. works like a champ. The other flange of the angle keeps the thing from collapsing under the pressure.
 

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lmsport said:
Did you use a new crush sleeve? because the sleeve locates on the pinion stem rather than just between the bearings, you have to use a new sleeve with every pinion change.
The crush sleeve plays no part in determing gear contact pattern, it only preloads the bearings.

Vince
 
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