Gear Whine?

[turboscrew]

I installed my 3.73s about 2 weeks ago. Used the instructions per superstallions.com and my dad(mechanic for 42 years) helped alot also. After the setup the backlash was .011" and the pinion depth was dead on. No whine at all until today but the only time I hear it is in 5th about 55-60 mph. I asked my dad and he said that probably any aftermarket gears are going to make some noise. Is this true?

My 2003 F150 has gear whine and I haven't touched it. It only has 25,000 miles and has done it since the day I bought it.


Is this noise hurting anything or am I just paranoid?

BTW I love the awesome pull from 3000 and up!!!

 

[Pughman]

my 3;73's (ford) have some wine to them...

 

[Jones331]

Re-check the backlash...jj

 

[Cobra Jay]

What kind of gears did you buy? FRPP's are aftermarket, but they're made by Ford.

The only gears that are really known to whine are Richmond.

Is the whine on the coast side (foot off accelerator) or drive side (accelerator applied)

Could be pinion pre-load,bearings,d/s bearings

Somethings not right. How many miles on car?

How long did you break-in the gears before you hammered on it?

Did you replace ALL (or any) of the bearings. Could be the carrier bearings or axle shaft bearings.

If I were you I'd take it back apart just to make sure.


As far as your truck goes, I'd take it back to the dealer. It will be covered under warranty. My 2003 F-150 FX4 goes in next week for a rear axle drive whine between 45-60. 33,000 miles. :damnit:

 

[hotmustang331]

You shouldnt have shimmed the pinion at all, leave the factory shim in there and reverse the spacers that align the carrier, even though they look the same in thickness it would only work if we reversed them. Thats exactly what we did and it worked perfectly, and the only whine I had was on our first test drive and even then very slight (50-55 only in 5th), it was probably wearing the paint off. It didnt whine after that. BTW me and my dad did the install. So that makes us able to work on almost any ford rearend, as we have put gears in an 8inch, 8.8inch, 9 inch, and a 7.5 inch. The only one with whine is the 7.5 because we didnt reverse the shims and it was too tight and it did whine so we were going to pull it down, but it got driven again by someone who didnt know there was a problem...SO it etched the whine into the gears. But no matter its pretty light and gets better as time goes on as it wears the gears in more and wears the old pattern out.

 

[bdcardinal]

if they were FRPP gears there shouldnt be any whine at all. gears shouldnt whine at all assuming they were setup correctly.

what fluid did you use when you filled up the diff? did you change it after 500 miles?

 

[turboscrew]

They are FRPP gears. I had to shim mine .10" to close up the backlash. When we reversed the shims it had .018" backlash. Soon as we added some to the left side and took some off the right the backlash was .011" Ford recommends .10"-.012".

I ran 3 heat cycles for 10 miles and then let cool for 30 min. Then sat overnight and haven't really gotten on them hard.

Btw the gears had 1,000 miles on them. They my have a different wear pattern to start with maybe thats why.

We just transferred the bearing and shim from the old pinion to the other and preloaded to 12 in./lb.

They only whine when accelerator is applied and the car has only 36,000 miles.
I used Lucas gearoil 85-140 plus the friction modifier.

 

[Mike97gt]

You shouldnt have shimmed the pinion at all, leave the factory shim in there and reverse the spacers that align the carrier, even though they look the same in thickness it would only work if we reversed them. Thats exactly what we did and it worked perfectly, and the only whine I had was on our first test drive and even then very slight (50-55 only in 5th), it was probably wearing the paint off. It didnt whine after that. BTW me and my dad did the install. So that makes us able to work on almost any ford rearend, as we have put gears in an 8inch, 8.8inch, 9 inch, and a 7.5 inch. The only one with whine is the 7.5 because we didnt reverse the shims and it was too tight and it did whine so we were going to pull it down, but it got driven again by someone who didnt know there was a problem...SO it etched the whine into the gears. But no matter its pretty light and gets better as time goes on as it wears the gears in more and wears the old pattern out.

no this is the wrong way to install gears.. even changing bearings let alone a ring and pinion is going too require the backlash and pinion depth too be reset.. since no two bearings or other rear end parts are the same..

many techs at my work do rear ends this way and i hate when they come back and i get stuck redoing them again..

 

[Mike97gt]

They are FRPP gears. I had to shim mine .10" to close up the backlash. When we reversed the shims it had .018" backlash. Soon as we added some to the left side and took some off the right the backlash was .011" Ford recommends .10"-.012".

I ran 3 heat cycles for 10 miles and then let cool for 30 min. Then sat overnight and haven't really gotten on them hard.

Btw the gears had 1,000 miles on them. They my have a different wear pattern to start with maybe thats why.

We just transferred the bearing and shim from the old pinion to the other and preloaded to 12 in./lb.

They only whine when accelerator is applied and the car has only 36,000 miles.
I used Lucas gearoil 85-140 plus the friction modifier.

why would you reuse the bearings... and you did'nt reset pinion depth with a new pinion

what you need too do is take the pinion back out... replace the pinion bearings and buy some crush collars... set the pinion depth right (at work we have a tube that bolts in place of the carrier and another tool that goes in place of the pinion... with both installed you use a feeler gauge and when you find the right one that fits snug you get that size shim)


BTW 12 in/lb tourqe is a little on the low side for the pinion pre load.. i never reuse old bearings but if i did i would go with 20 in/lb... with new bearings ( i always do it this way) 24in/lb

i dont blame your dad for not wanting too resetup the pinion.. a lot of times it will be ok and without the special tools that make it easy, pinion depth setup can be a bitch...

i would recheck the carrier too after you setup the pinion... your backlash will change a little after this... hopefully you will still be in range but it is still worth it too check..

 

[turboscrew]

Well the bearings only had 35,000 miles on them so I figured they should be ok. Ford recommended 12 in./lb for a used bearing and 20-25 for a new bearing.

 

[Kilgore Trout]

Take it to the dealer or a good speed shop and have them fix your work.

 

[loosescrew79]

pull the 3.73s out and go 4.10...

 

[Cobra Jay]

I'd pull everything apart and try again. If it still whines, I'd ditch the bearings, R&P buy some new parts and have it done by someone who does rear axles for a living.

 

[COramprat]

Why oh why when someone asks legit questions you get answers like the above trout ans loosescrew...geez guys help or stay out...

 

[Kilgore Trout]

I though I was helping!