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Drivetrain Help with new GEARS

  • Thread starter Thread starter AbhorrentSpecies
  • Start date Start date Aug 6, 2021
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AbhorrentSpecies

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Aug 6, 2021
#1
  • Aug 6, 2021
  • #1
Hey guys. So I just had a new gears installed on my car this Thursday. They did the ring and pinion, 3.55s, I had them redo the bearings, seals, clutch pack, new axles, axle seals and bearings, the whole nine. After test driving the car I noticed a slight rhythmic clunk sound when turning sharp right. They said it was normal for having new clutch pack and gears. Now having done the break in, 15 miles, 30 mins rest for a total of 45 miles. Then driving another 15 miles. I'm now at 60. I'm starting to hear grinding while going about 30 and turning slight right as well as the rhythmic clunk doing slow turns in a parking lot. This doesn't seem normal to me. Anyone, please advise if I need to bring this back to them or what could be the issue or is this normal with new gears/clutch pack??? Thanks!
 

91AOD5.0LX

I have a slight sag in my rear
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Feb 20, 2021
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Lake George NY
Aug 6, 2021
#2
  • Aug 6, 2021
  • #2
AbhorrentSpecies said:
Hey guys. So I just had a new gears installed on my car this Thursday. They did the ring and pinion, 3.55s, I had them redo the bearings, seals, clutch pack, new axles, axle seals and bearings, the whole nine. After test driving the car I noticed a slight rhythmic clunk sound when turning sharp right. They said it was normal for having new clutch pack and gears. Now having done the break in, 15 miles, 30 mins rest for a total of 45 miles. Then driving another 15 miles. I'm now at 60. I'm starting to hear grinding while going about 30 and turning slight right as well as the rhythmic clunk doing slow turns in a parking lot. This doesn't seem normal to me. Anyone, please advise if I need to bring this back to them or what could be the issue or is this normal with new gears/clutch pack??? Thanks!
Click to expand...
I had my gears done in March. 4:10. No grinding, thumping or any other kind of noises etc. I’m sorry this is happening to you but in comparison
To my experience I say bring it back because that doesn’t sound normal to me at all. I had no noises before or after the break in period. I wouldn’t want to see you damaging any internal parts by driving like that. Bring it back to them.
 
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AbhorrentSpecies

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Jun 14, 2020
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#3
  • Aug 6, 2021
  • #3
91AOD5.0LX said:
I had my gears done in March. 4:10. No grinding, thumping or any other kind of noises etc. I’m sorry this is happening to you but in comparison
To my experience I say bring it back because that doesn’t sound normal to me at all. I had no noises before or after the break in period. I wouldn’t want to see you damaging any internal parts by driving like that. Bring it back to them.
Click to expand...
That's exactly what I think I'll be doing. Did you happen to have new clutch packs put in as well? Cause that's what they blamed the noise on initially.
 

91AOD5.0LX

I have a slight sag in my rear
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#4
  • Aug 7, 2021
  • #4
AbhorrentSpecies said:
That's exactly what I think I'll be doing. Did you happen to have new clutch packs put in as well? Cause that's what they blamed the noise on initially.
Click to expand...
Yes I did.
AbhorrentSpecies said:
That's exactly what I think I'll be doing. Did you happen to have new clutch packs put in as well? Cause that's what they blamed the noise on initial
Click to expand...
AbhorrentSpecies said:
That's exactly what I think I'll be doing. Did you happen to have new clutch packs put in as well? Cause that's what they blamed the noise on initially.
Click to expand...
No. According to the receipt I didn’t get clutch packs. They did as follows:
Small 8.8 pinion flange, pinion seal, large pinion race and bearing, small pinion race and bearing, conventional gear oil, friction modifier 3.8oz bottle, gasket maker and gear oil green, and gear set and the 23 tooth speedometer gear.
I still don’t buy that yours is suppose to sound and act like that just because you did clutch packs. Go back and talk to them....
 

91AOD5.0LX

I have a slight sag in my rear
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#5
  • Aug 7, 2021
  • #5
Sorry looks like I posted a few posts in error.
I didn’t get clutch packs. Disregard that post that says yes. I only got the stuff listed on the receipt that I sent in my last post
 
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AbhorrentSpecies

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#6
  • Aug 7, 2021
  • #6
Thanks, I appreciate it.
91AOD5.0LX said:
Sorry looks like I posted a few posts in error.
I didn’t get clutch packs. Disregard that post that says yes. I only got the stuff listed on the receipt that I sent in my last post
Click to expand...
 

manicmechanic007

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#7
  • Aug 7, 2021
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Assuming the shop assembled it correctly. It just needs another bottle of ford friction modifier. It sure sounds like you are describing clutch chatter. Whether you got new clutch packs or not it needs the friction modifier. It needs more than the book says. The book says you add 1 tube bottle. Used to have to add about three bottles total to get a posi 88 to shut up. Figure eights in the parking lot to get it hot several then add a bottle and repeat retest. Add another bottle and repeat
 
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AbhorrentSpecies

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#8
  • Aug 7, 2021
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manicmechanic007 said:
Assuming the shop assembled it correctly. It just needs another bottle of ford friction modifier. It sure sounds like you are describing clutch chatter. Whether you got new clutch packs or not it needs the friction modifier. It needs more than the book says. The book says you add 1 tube bottle. Used to have to add about three bottles total to get a posi 88 to shut up. Figure eights in the parking lot to get it hot several then add a bottle and repeat retest. Add another bottle and repeat
Click to expand...
It has at least one bottle and the royal purple gear oil already has modifier in it. I had the same exact oil and modifier in my previous 8.8 and never heard anything. You saying it needs more? Seems like overkill. Why wouldn't the shop have recommended this?
 

manicmechanic007

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#9
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Yes I am saying it needs more. Good choice of expensive purple but add the Ford modifier. as to why the shop did not say.. Maybe this is their first rodeo with a chattering limited slip ford. Maybe they did not get the memo. There was a TSB back in about 95 for Bronco and F150 88's to do just that... Add more
I assume they assembled it correctly
 

AbhorrentSpecies

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#10
  • Aug 7, 2021
  • #10
manicmechanic007 said:
Yes I am saying it needs more. Good choice of expensive purple but add the Ford modifier. as to why the shop did not say.. Maybe this is their first rodeo with a chattering limited slip ford. Maybe they did not get the memo. There was a TSB back in about 95 for Bronco and F150 88's to do just that... Add more
I assume they assembled it correctly
Click to expand...
Well they've been in business for 40 years. I'm pretty certain they have rebuilt many ford diffs. Either way, doesn't hurt to try another bottle. Thanks!
 

manicmechanic007

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#11
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It makes no noise going straight right? 40 years is great not faulting the shop. The book says add 1 bottle or use the premix stuff. It is Me that says add more and that is from my experience as a 20 year Ford dealer tech. I sure do not know it all. I have however fixed a ton of Fords. I am often sceptical myself about putting too much in thinking the limited slip will start slipping before the torque spec. But I have never had a problem with that. Hopefully 90sickfox will chime in
 

91AOD5.0LX

I have a slight sag in my rear
5 Year Member
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#12
  • Aug 7, 2021
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The Ford modifier is verry important.
friends of mine with MOPAR cars say they put the Ford modifier in the MOPAR rears and if not it’s a hot mess! Listen to Manic, he’s on to something!
 

General karthief

wonder how much it would cost to ship you a pair
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#13
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I had my clutch packs and a set of bearings and gears, 3.55, done 35k+ miles ago, quiet, only sound I hear is the tires try'n to rip chunks of the road surface out in anger.
Royalpurple and one bottle of modifier.
I will say I'm a lucky dog when it comes to repair/rebuilding stuff.
 
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AbhorrentSpecies

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  • Aug 7, 2021
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manicmechanic007 said:
It makes no noise going straight right? 40 years is great not faulting the shop. The book says add 1 bottle or use the premix stuff. It is Me that says add more and that is from my experience as a 20 year Ford dealer tech. I sure do not know it all. I have however fixed a ton of Fords. I am often sceptical myself about putting too much in thinking the limited slip will start slipping before the torque spec. But I have never had a problem with that. Hopefully 90sickfox will chime in
Click to expand...
At first it just knocked when doing a sharp right turn, like you said in a parking lot. But after driving conservatively for 45 miles, then it started chattering at higher speeds. It would only do it when turning slight right like around the bends in my neighborhood. Especially so when I'm at lower rpms. Then when you straighten out it continues to clatter for a bit but then stops.
 

manicmechanic007

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#15
  • Aug 8, 2021
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Wear gloves when you deal with the Ford modifier or you will not get laid for a week. It stinks bad. Used to tell customers.... That's those clutch packs working for you sir. Then put the modifier in and he will not know if they are working or not because it would be silent after that. They make a ton of noise without enough modifier. Add a bottle and retest
 

AbhorrentSpecies

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#16
  • Aug 8, 2021
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manicmechanic007 said:
Wear gloves when you deal with the Ford modifier or you will not get laid for a week. It stinks bad. Used to tell customers.... That's those clutch packs working for you sir. Then put the modifier in and he will not know if they are working or not because it would be silent after that. They make a ton of noise without enough modifier. Add a bottle and retest
Click to expand...
Yeah, that stuff smells horrible. Also, don't worry, I'm married, I already don't get laid. So have I damaged the clutch packs too much already or should they be fine? I've only driven about 60 miles.
 
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manicmechanic007

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#17
  • Aug 8, 2021
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Clutch packs will be fine. lol about the wife I have to chase mine around too
 
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AbhorrentSpecies

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#18
  • Aug 8, 2021
  • #18
manicmechanic007 said:
Clutch packs will be fine. lol about the wife I have to chase mine around too
Click to expand...
So I just went under the car to add friction modifier and it definitely looks like they filled it with the royal purple I brought them. Not sure if they used the modifier but when I took off the fill bolt, it hissed at me like there was a punch of pressure in the diff. Hasn't been driven since Friday. Also, there was a bunch of metal shavings all over the magnetic part of the bolt. Is that normal for a new diff? Seemed excessive to me. Like it was really gritty.
 

AbhorrentSpecies

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#19
  • Aug 8, 2021
  • #19
manicmechanic007 said:
Clutch packs will be fine. lol about the wife I have to chase mine around too
Click to expand...
I stopped chasing her when we got married. She can have some whenever she wants. She knows where I am. I'll either be on the couch or under the car lol.
 
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General karthief

wonder how much it would cost to ship you a pair
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#20
  • Aug 8, 2021
  • #20
AbhorrentSpecies said:
So I just went under the car to add friction modifier and it definitely looks like they filled it with the royal purple I brought them. Not sure if they used the modifier but when I took off the fill bolt, it hissed at me like there was a punch of pressure in the diff. Hasn't been driven since Friday. Also, there was a bunch of metal shavings all over the magnetic part of the bolt. Is that normal for a new diff? Seemed excessive to me. Like it was really gritty.
Click to expand...
stick a skinny finger in the fill hole and get a sample of the oil, maybe spin the wheels a few revolutions to stir it up, some junk on the magnet would not be unusual, clean it off, it's easy enough to check again later on.
Toss another bottle of modifier in there and run some slow figure 8s, just need 3 or 4 rounds. Let us know how it goes. Or not goes.
 
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