My wife has 97 F150 4x4 Supercab with 3.55 ratio limited slip rear, 71,000 miles. The problem is that a couple of weeks ago the vehicle started making noise that sounds like it has real aggressive or uneven tire tread. Tonite I put the vehicle up on jack stands and my wife "drove" it while I listed under the vehicle. I tried to use a piece of plastic hose to "listen" for the noise. I was able to tell the noise is coming from the rear half of the vehicle, but I could not tell where. Any suggestions?? Thanks!

 

It might be possible your limited slip rear axle needs some 1) friction modifier, 2)fluid replaced with friction modifier.

There has been a good deal of talk about this (if it is indeed your LS)...try a search on the limited slip topic and see what you find.

I decided NOT to go with LS when I ordered my 2000 for this reason. Other members posted that they were hearing 'noises' from the rear gears when making turns..etc.

------------------
2000 F-150 XLT, 4x2, 5.4L Supercab, Styleside, Black with silver two-tone, 3.55, class III towing package with heavy duty cooling package, 4 wheel disk ABS, overhead console, sliding rear window, keyless entry, dark graphite interior, in dash CD, Pendaliner bedliner, K&N air filter, rubberized undercoating, cabin filtration system, Bugflector II, 5W-30 Mobil 1, engine build 10/4/99

 

Did you try spinning the tire's by hand when it was on the jack stands. Could be your rear brake drums are causing the noise. Rust-shoes-adjudtment ect... sure sounds like a moving part look carefully at driveshaft and tires even a hole in the muffler in the right location could create the noise....something small could be wrapped around or hung up under the truck do you have oversize tires? Mud flaps? lifted?lowered? Tell us more..Do you haul or tow heavy loads... Not a mechanic just trying to give you a few idea's... Please be very careful under that truck a little noise is not worth a life time of pain. No speaches just BE CAREFUL! And good luck..Capt.

------------------
Capt. America..,
1998 F-150 XLTSC...2WD.. . 4.10LS rear...auto E40D... 5.4L...Flairside... Ground effects... Billet Pedals... Billet Grill... Billet Brake lite... Oval Mirror... Bed rails... Bug Deflector... Wood Grain Kit...Fog lites... TPS...Velocity tube... K&N... ss Ford tag.,.Tinted Windows... overhead/floor consoles... Mood lights...Blue bulbs... Alarm...Radar...Dashmat... Fire/Ice rear window tint ...conspicuity reflectors... cd changer...mobil 1... Painted rear Drums... Helwing Sway Bar... Dual Exhaust... Halogen Back-up bulbs... clear corner lens...
Tail lens covers... Leather...Floor Mats... Seat covers...Tow Pkge...
Side window Louvers... Painted Brake calipers... Custom Captian America Paint Job...TRIPLE LED brake lights...Rain guards... Painted throttle body cover...sliding rear window...Superchip...Custom Gas cap holder...2" leveling shackels...Fox tail key chain...Clear turn signal bulbs..

 

Hey Capt America,
In your profile, You mention fire/ice rear window tint.
What is that? and Where did you get it?
Thganks,
AHAB

 

AHAB- Fire/ice window tint was purchased from auto zone. It's really neat on my color truck. It appears like dark tint with a glitter 3d effect when seen from different angles or when the sun hit's it just right. Colors in tint scroll from red to blue to green to silver. My rear window was a dark tint from factory paper was almost clear. They also had other types in different styles. I also cosidered the full sceen's sold by jc whitney. They really looked nice but my rear window has a slider and thought it would be hard for me to cut and match to make it look good. Everyone loves the way my window looks. It worked out well for me.... Capt. I wonder when someone is going to want and see a picture of the triple led lights. Best mod so far if you have bed rails. Hmmmm maybe I'll just keep that one for myself...Naaa

[This message has been edited by CAPT. AMERICA (edited 02-26-2000).]

 

Additional info. When truck was on jack stands, I removed tires and brake drums. I saw no unusual wear on brake shoes and no evendence that the brake drums were rubbing against the backing plates. I used a piece of plastic hose as stethoscope on the differential and the brake backing plates, but was unable to locate the exact source of noise. The noise is obvious even at low speeds, like 10mph. The noise sounds like your driving with huge mudder tires on it.
There are no foreign materials around the moving parts and the vehicle is at factory ride height for 4x4. It has occasionly pulled a 2000 lb trailer. I'm guessing that it is one of the following, rear ujoint, rear axle bearings, worn differential, but no evidence to back it up. Any suggestions??

 

The rear diff. on my new 2000 xlt.5.4 limited slip had to be reworked. $987.00 worth, fact.warr. 9 days to do it. Because of the wine at 40 to 50mph. And it still wines, a little bit quieter. They say now, that its normal ?

 

Did you check your U-joints? When they go bad, they make all kinds of sounds. From squeaking to rumbling to clunking to rattling.

 

Mine does the exact same thing. It gets worse. I haven't been able to get it into the shop yet. Mine sounds like I've got big ol' mudder tires on doing 100 down the freeway.

------------------
98' F-150, Off Road, Short Box, Blue, 4.6, K&N, Auto, Captain Chairs, Dual Exhaust
Alpine CD Player, (2) 10" Rockford Fosgate Subwoofers and a big ol' Arctic Cat
sticker on the rear sliding window!!!!! Soon to be chipped!!!

 

Different gear ratios are more prone to noise than others -- and are affected by poor set-up and/or wear and/or poor manufacturing.

What ratio do you have (making noise)? Is it on the 'Drive' or 'Coast' side (Drive = under power -- can be either just keeping the truck at speed, or can be while accelerating; Coast is with food off gas)?

I've spent a lot of time listening to gear noise -- and my new 2K has a barely-detectible gear whine when holding at speed -- nothing under coast, and nothing under power. I plan on leaving it alone.

Unless it [yours] changes, I suggest that you learn to love it or be prepared to have someone less smart than you are working on it for you -- on your dime.

They will make A LOT of noise before they come even remotely close to failure.



------------------
XLT SC SB 5.4 4x4 3.73 LS

 

Mine does it all the time, while under power or coasting. Hopefully Ford will take care of it because there's no way they could tell me it's normal. It started making the noise at 33xxx about a month after they fixed a leak in the rearend. It's leaking again but it's not low on lube.

------------------
98' F-150, Off Road, Short Box, Blue, 4.6, K&N, Auto, Captain Chairs, Dual Exhaust
Alpine CD Player, (2) 10" Rockford Fosgate Subwoofers and a big ol' Arctic Cat
sticker on the rear sliding window!!!!! Soon to be chipped!!!

 

My 97 has same/similar whine at all speeds coming somewhere from the bottom. Couple shops told me it's the tires. But that's what they are selling.
I was thinking about the drive shaft more.
But cannot pinpoint. This whine is speed dependent, not RPM. It all started after a long trip last year. It's annoying.

 

Sounds like they boogered-up the pinion adjustment when they replaced the pinion seal. They're in for a biggie. Good luck.

 

Hey ford fixer, do you have an answer for the limited slip wine ?