Ideas to quiet down the rear end or driveshaft?
11-18-2013, 05:34 PM
#22
Burning Brakes
I wonder if the gear set is installed off a little bit.
I paid a lot of $$, but have 2 ikerd rear ends. One is a 3:73, and the other a 4:10 gear set.
They are both quiet as stock. Maybe call them and ask what they think.
I paid a lot of $$, but have 2 ikerd rear ends. One is a 3:73, and the other a 4:10 gear set.
They are both quiet as stock. Maybe call them and ask what they think.
11-19-2013, 09:21 AM
#23
Depending on your local salvage yards and maybe "taxi fleets" there should be many around. The price should be negotiable. Now not all "taxi fleets" would have P71 cars, theirs would be P72 cars but they bought old cruisers as soon as they became available also. I found many available.
The stripes are the telling tale and I understand that some had a label "POLICE MMC" wrapped around the early shafts.
Use: www.car-part.com and the drop-downs select rear driveshaft and you'll see the option to choose CVPI and you'll see 2 date options, I chose the later but you could use both and assume maybe someone doesn't understand what they have. Pay no attention to the prices you see- they're very negotiable and all you want is the shaft - no slip yoke etc so your choices could improve.
An OE number FMC: XW7Z-4602-AA
Remember now that I didn't mention this to be "a fix" - it's the approach you mentioned you wanted to take!! One of these and gluing in the liner also would be the max to expect for "resonance removal"!
Last edited by WVZR-1; 11-19-2013 at 09:24 AM.
11-19-2013, 10:55 AM
#24
Racer
Thread Starter
I believe I have and the CVPI/P71 (Crown Vic Police Interceptor/P71 is the VIN designator digits 6 & 7) in '99 & '00 for sure had the MMC shaft and parts publications mention through '03. The parts publications mention that all would have pink, green & blue stripes.
Depending on your local salvage yards and maybe "taxi fleets" there should be many around. The price should be negotiable. Now not all "taxi fleets" would have P71 cars, theirs would be P72 cars but they bought old cruisers as soon as they became available also. I found many available.
The stripes are the telling tale and I understand that some had a label "POLICE MMC" wrapped around the early shafts.
Use: www.car-part.com and the drop-downs select rear driveshaft and you'll see the option to choose CVPI and you'll see 2 date options, I chose the later but you could use both and assume maybe someone doesn't understand what they have. Pay no attention to the prices you see- they're very negotiable and all you want is the shaft - no slip yoke etc so your choices could improve.
An OE number FMC: XW7Z-4602-AA
Remember now that I didn't mention this to be "a fix" - it's the approach you mentioned you wanted to take!! One of these and gluing in the liner also would be the max to expect for "resonance removal"!
Depending on your local salvage yards and maybe "taxi fleets" there should be many around. The price should be negotiable. Now not all "taxi fleets" would have P71 cars, theirs would be P72 cars but they bought old cruisers as soon as they became available also. I found many available.
The stripes are the telling tale and I understand that some had a label "POLICE MMC" wrapped around the early shafts.
Use: www.car-part.com and the drop-downs select rear driveshaft and you'll see the option to choose CVPI and you'll see 2 date options, I chose the later but you could use both and assume maybe someone doesn't understand what they have. Pay no attention to the prices you see- they're very negotiable and all you want is the shaft - no slip yoke etc so your choices could improve.
An OE number FMC: XW7Z-4602-AA
Remember now that I didn't mention this to be "a fix" - it's the approach you mentioned you wanted to take!! One of these and gluing in the liner also would be the max to expect for "resonance removal"!
Jim G
11-19-2013, 06:59 PM
#26
Racer
Thread Starter
No lesson learned I'm afraid. The results in nimbleness of the car are SO good that I would do it again without even hesitating. If you've never driven a C4 automatic "stock" and "regard", you are missing one of the great transformations.
The noise even unaddressed is not really that "bad". It's there, but not a huge distraction. I often forget it is there.
Jim G
The noise even unaddressed is not really that "bad". It's there, but not a huge distraction. I often forget it is there.
Jim G
11-19-2013, 07:12 PM
#27
Le Mans Master
Jim, years ago, the first mod I did was change the 2.59 rear for a 3.54 rear built by zip products. It was as quiet as the factory rear, ie, no noise at all. The car was bone stock. I do agree, with a LT1 its about the best single mod to be done. I ran 13.17 ets on mich. pilot tires. Latter added a 3000 stall yank converter and ran 12.91 et. But as you said, the 3.54 gear really makes the LT1 a different car.
11-20-2013, 05:20 PM
#28
Race Director
Hope you prove me wrong.
-Mike
11-20-2013, 07:29 PM
#29
Racer
Thread Starter
And, I really don't have any good alternative choices. The installer is a very experienced guy who got it as perfect as he could. Sure, the gear set might have in some way been less than perfect for all I Know, but it makes no financial sense to pay the shop to take everything apart, wait for Richmond Gear to agree it's gear set is somehow imperfect, and then pay to put everything together again, and the car, my daily driver and ONLY car, being out of service for however long all THAT takes!
And, remember, the change of driveshaft is precisely what fixed the SSR, and the SSR reared and driveline was running fine for tens of thousands of miles after the driveshaft swap.
I'm acting on the best info and best evidence available to me.
Jim G
11-22-2013, 03:22 PM
#30
Safety Car
If you want to try a temporary test of your driveshaft resonance theory, you might consider spiral wrapping the driveshaft with duct tape. Wrap each end again to keep the tape from peeling off by considering how the airflow will try to peel the tape (CW or CCW wrap). (I've even seen "duct tape" that looks like carbon fiber, if you want to go fancy!).
Last edited by Hot Rod Roy; 11-22-2013 at 03:25 PM.
11-22-2013, 04:11 PM
#31
Racer
Thread Starter
If you want to try a temporary test of your driveshaft resonance theory, you might consider spiral wrapping the driveshaft with duct tape. Wrap each end again to keep the tape from peeling off by considering how the airflow will try to peel the tape (CW or CCW wrap). (I've even seen "duct tape" that looks like carbon fiber, if you want to go fancy!).
Actually, the driveshaft behaves like a musical instrument. A guitar makes sound when a string is strummed while being held by a finger at one point. The driveshaft when "excited" by a mechanical input while rotating, makes "music". So, it is also likely that simply mounting a metal clamp around any point on the driveshaft, could appreciably dampen the noise. A trial and error process could in theory find a point to apply the clamp that results in non-audible "music".
Jim G
11-22-2013, 05:16 PM
#32
Le Mans Master
....... Non-audible music !?!? ......... My solid rollered , Hooker-headered , X-piped 3inch exhaust through Flowmasters pumps out the most awesome symphony I've ever heard .......... shame on you ........
11-22-2013, 08:21 PM
#33
I don't see it that interesting. The drive-shaft needs removed to accomplish the "wrap" so I don't know why you wouldn't do the balance confirmation and inspect u-joints and dampener like I mentioned anyway. If it were a conventional RWD vehicle with an exposed drive-shaft the "wrap" might show promise but I don't see it being a viable diagnostic tool here. Way to labor intensive for the test. This is a drive-shaft that is tubing wise likely 24" long. After the "wrap" you install and I don't know how convincing the "wrap" could be but then it's another removal to do the MMC anyway.
Way back in #11 I mentioned the electronic diagnostics that are available to accomplish I believe the diagnostics. There's a Kent-Moore wired and also "wireless" "Listening Tool" that might be the "tell all".
The wired a KM J-39570 and the "wireless" J-48716 that I would guess either could be set up in less that an hour and a thirty to fifty mile drive I would think could "nail the source" for all concerned Jim the owner, the builder of the rear and the guy who's maybe going to be the MMC drive-shaft fabricator. Is the MMC drive-shaft the answer? I'm inclined to believe it's the build but I'd like to be proved wrong. I know that the MMC solved Ford's issues and Jim's convinced it did his SSR. Both have substantially longer drive-shafts that allowed the flex. The MMC removed the tendency to flex and resonate.
Why the thirty to fifty mile drive? I would think it ideal to start with "dead cold" to what we could determine to be normal highway temps of the rear. This being Jim's only driver how do you accomplish this. I'd think he and the builder could work that out. Who does the "set-up"?
Way back in #11 I mentioned the electronic diagnostics that are available to accomplish I believe the diagnostics. There's a Kent-Moore wired and also "wireless" "Listening Tool" that might be the "tell all".
The wired a KM J-39570 and the "wireless" J-48716 that I would guess either could be set up in less that an hour and a thirty to fifty mile drive I would think could "nail the source" for all concerned Jim the owner, the builder of the rear and the guy who's maybe going to be the MMC drive-shaft fabricator. Is the MMC drive-shaft the answer? I'm inclined to believe it's the build but I'd like to be proved wrong. I know that the MMC solved Ford's issues and Jim's convinced it did his SSR. Both have substantially longer drive-shafts that allowed the flex. The MMC removed the tendency to flex and resonate.
Why the thirty to fifty mile drive? I would think it ideal to start with "dead cold" to what we could determine to be normal highway temps of the rear. This being Jim's only driver how do you accomplish this. I'd think he and the builder could work that out. Who does the "set-up"?
Last edited by WVZR-1; 11-22-2013 at 09:12 PM.
11-22-2013, 10:10 PM
#34
Racer
Thread Starter
I don't see it that interesting. The drive-shaft needs removed to accomplish the "wrap" so I don't know why you wouldn't do the balance confirmation and inspect u-joints and dampener like I mentioned anyway. If it were a conventional RWD vehicle with an exposed drive-shaft the "wrap" might show promise but I don't see it being a viable diagnostic tool here. Way to labor intensive for the test. This is a drive-shaft that is tubing wise likely 24" long. After the "wrap" you install and I don't know how convincing the "wrap" could be but then it's another removal to do the MMC anyway.
Way back in #11 I mentioned the electronic diagnostics that are available to accomplish I believe the diagnostics. There's a Kent-Moore wired and also "wireless" "Listening Tool" that might be the "tell all".
The wired a KM J-39570 and the "wireless" J-48716 that I would guess either could be set up in less that an hour and a thirty to fifty mile drive I would think could "nail the source" for all concerned Jim the owner, the builder of the rear and the guy who's maybe going to be the MMC drive-shaft fabricator. Is the MMC drive-shaft the answer? I'm inclined to believe it's the build but I'd like to be proved wrong. I know that the MMC solved Ford's issues and Jim's convinced it did his SSR. Both have substantially longer drive-shafts that allowed the flex. The MMC removed the tendency to flex and resonate.
Why the thirty to fifty mile drive? I would think it ideal to start with "dead cold" to what we could determine to be normal highway temps of the rear. This being Jim's only driver how do you accomplish this. I'd think he and the builder could work that out. Who does the "set-up"?
Way back in #11 I mentioned the electronic diagnostics that are available to accomplish I believe the diagnostics. There's a Kent-Moore wired and also "wireless" "Listening Tool" that might be the "tell all".
The wired a KM J-39570 and the "wireless" J-48716 that I would guess either could be set up in less that an hour and a thirty to fifty mile drive I would think could "nail the source" for all concerned Jim the owner, the builder of the rear and the guy who's maybe going to be the MMC drive-shaft fabricator. Is the MMC drive-shaft the answer? I'm inclined to believe it's the build but I'd like to be proved wrong. I know that the MMC solved Ford's issues and Jim's convinced it did his SSR. Both have substantially longer drive-shafts that allowed the flex. The MMC removed the tendency to flex and resonate.
Why the thirty to fifty mile drive? I would think it ideal to start with "dead cold" to what we could determine to be normal highway temps of the rear. This being Jim's only driver how do you accomplish this. I'd think he and the builder could work that out. Who does the "set-up"?
Jim G
11-23-2013, 05:08 PM
#35
Melting Slicks
I dunno, I'd try some easy / inexpensive stuff first. If you haven't already done so, change out the lube in the differential; especially if it's still the original "break in" lube; try some different lube types; maybe something a little heavier; I suggest you try RED LINE "shock proof" differential lube.
If you go to the trouble of pulling the drive shaft; pull the tailshaft housing off the rear of the transmission and replace the tailshaft bushing and rear seal; any wear there (and there's certain to be some) will only add to the perceived drive shaft noise.
As a final option, pull the differential, after initial wear in, some minor readjustment might be in order.
finally, turn up the radio
If you go to the trouble of pulling the drive shaft; pull the tailshaft housing off the rear of the transmission and replace the tailshaft bushing and rear seal; any wear there (and there's certain to be some) will only add to the perceived drive shaft noise.
As a final option, pull the differential, after initial wear in, some minor readjustment might be in order.
finally, turn up the radio
04-15-2014, 04:30 PM
#37
Racer
Sorry to resurrect a 5 month old thread Jim but did your noise issue ever get resolved? 80W140? New drive shaft? wrong pinion setting? bad pinion bearing? bad gear set?
04-15-2014, 04:49 PM
#38
Do you have issues or just an inquiring mind?
04-15-2014, 10:23 PM
#39
Racer
Thread Starter
Jim G
04-16-2014, 01:25 PM
#40
Racer
"My '84-z51, (D36-3.07 gear), is making a high pitched warbly whining noise when i'm applying the throttle but quiets down when I take my foot off the gas. I'm not sure if it's the diff, bearings, u-joints, or what? The pitch and the warble frequency both increase with speed. By "warbly" I mean a constant amplitude or intensity modulation (pulsation). I'm thinking pinion bearing wear but a friend thought it sounded more like u-joints. Any acoustic experts on drive train noises out there?"
Just wondering if the OP had resoved his noise issue and whether just using 80W140 would help mine. Fairly certain it's not coming from the drive shaft or u-joints.