2008 F350 Rear End Whine

[johnny9r]

I have 2008 F350 with 62k on it a moaning noise coming from my rear end when slightly on power, it goes away when I lift off the gas. I took this into my local dealer and he told me he thinks it is the rear end gear that is going bad because it was not properly shimmed at the factory. The crummy part is the powertrain warranty just ended at 60k miles so he has estimated that is a $3,000.00 job to fix the sucker.

My questions are is there any hope in reaching out to ford and letting them know this probably was there before the warranty expired and hope they will cover it?

Secondarily does $3,000.00 sound like a correct figure for this kind of job? The service guy mentioned that there was like $2500.00 in parts to get this done.

Would you trust anyone other than Ford to make this change?

Help with thoughts on this.

Johnny9r

[ZeroOne]

$3,000!?!? Is this a dually or single rear wheel?? Ratio?

For a single rear wheel (10.5" axle), I'd say $1,500 max, for OEM gears, bearings, fluid, labor.

Ford OEM gears are more expensive and are said to be quieter. They cost around $450-$550, plus $300 for an install kit. That's only around $900 in parts and shipping. Installation labor costs vary, but I don't think it's an all-day job. Maybe 4-5hrs of labor? So another $500 or so, and $75 in fluid if I remember correctly. That $#!t is expensive for some reason. 75w140syn.

I have yukon in mine and can't hear them at all. They were installed at an offroad jeep / truck shop. We did have a small installation issue, which they covered, and all is well. You do have to make sure the shop has experience because the tolerances are very specific.

I have no idea why they quoted you for three thousand dollars though. That's insane.

Check out this website for parts and prices.... Randy's Ring & Pinion. The Differential Experts. Auto Parts & Services.

[ZeroOne]

Just wanted to add.... besides all of the numbers above... who says your gears are toast, really? Maybe the pinion bearings are shot, affecting the pinion preload or proper gear mesh? What I posted above is worst-case. You could still argue the warranty angle. Worth a shot anyway.

[johnny9r]

It is a single rear axel. Any idea how I can dteremine the gear ratio? I bought the truck used so I don't have the original sticker.

[ZeroOne]

There should be a metal tag hanging from one of the rear diff cover screws. That tag should show the ratio on it. From your description (single rear wheel, '08, diesel I assume), it is most likely a 3.73 ratio in a Ford 10.5 rear. Which package do you have? Is it an FX4? You also may or may not have the limited slip rear end. I think it's standard on the FX4 model though. You'd need to know this to determine whether or not you need a small bottle of friction modifier when refilling the differential after the work is complete. Not hard to figure out though.

[johnny9r]

Lariat. Model would the limited slip be on that tag as well?

[Strokin'_AK]

There should be a data tag under one of the cover bolts. It will have the ratio stamped on it. Mine, for instance, has 3L73, which means it is a 3.73 ratio with limited slip. If the data tag is gone, you can always jack up the rear end, spin the driveshaft to make one full revolution of the tires, and count how many times you have to spin the driveshaft to complete that one full revolution of the axle. Obviously, it's going to be hard to count that final ".73" of a turn, so some estimation will be necessary. Hope this helps.

[johnny9r]

Lariat model. Would the limited slip stuff be on tghere as well? If it matters it is a cc lb

[ZeroOne]

It may be... but to be honest, I can't remember how everything is written on the tag. When you go under there to check it out, just write down everything. There isn't much. Look for the 3.73, and keep an eye out for "LS" anywhere.

The dealer can also run your VIN number and give you that information as well.

[JMart]

try to google the vin it may produce a window sticker somewhere.