07 F-150 Rear Differential/Drive Shaft Leak

Okay, first of all let me start by saying. I have no idea if this is a website for stuff like this… I’ve been looking at a place forever to try to find answer or even post my pictures about stuff like this… If it’s not then I’m sorry. If it is then great I hope one you vehicle gurus can tell me whats up.

Okay, so I know a little bit about working on my vehicle. Which all of my knowledge involves being under the hood of it, not underneath the actual vehicle itself. So anyways here’s my story… I bought this truck used. It has had problems out of the gate; needing a lot of stuff (tires, battery, ac motor…etc) and it’s seeming to be just a money pit!!! Anyways, today I was driving home from work and it was seemingly like any other day, then I notice like a light howl or whine coming from the back of my truck. I pull over and see if I hooked a bag or something go stuck under my truck. Nothing. I proceed to continue down the road and in a matter or like 20 minutes it went from a light howl to me turning up my volume extremely high just to drown out the loud and ear throbbing howling of my truck… Soooo. I am about 10 minutes from home when all the sudden anytime I press the accelerator my truck vibrates horribly. I managed to get home coasting most of the way and not managing to go over 20 mph. I put my truck in park, throw my emergency brake on and put some blocks behind my tires.(my driveway is steep) I immediately try any mechanics shop I can find. I manage to get find one open just to get an idea of whats wrong with my truck. He told me that (with the pictures I sent him) that I needed and hole new differential, gears, and bearings… Which would cost me over $1500… I don’t make a whole lot and my truck is my lifeline for my work. I guess with what I’m looking for here is either an idea of how to fix it and what not to fix(granted you don’t know what is damaged behind the differential cover) so I don’t sound sooo “well Im don’t know much about cars” and the mechanics shop is like “oh we also installed some blinker fluid” at a low low price of $150… Ya know just a bunch of hidden charges… or an idea of just a more realistic estimate with what you see in the pictures… unless 1500 sounds about right ><

Someone really gave an estimate just by looking at pictures? Probably not a good idea making snide remarks about mechanics when seeking advice.

I’ve always had an uncle or family member that knew something about vehicles and they helped me, I recently relocated and don’t have that luxury anymore. I’ve never been to a mechanics shop. I’ve had a friend tell me that they’ve added stuff here and there just to get more money. Not the actual “blinker fluid” thing. But other stuff… So it does happen… All I was stating is that I didn’t want it to happen to me, not saying every mechanic is a crook or out to bleed money from ever person that pulls into there garage but it does happen. Sorry If I offended anyone…

That’s a pinion seal leaking and if the pinion bearing is not worn out a new seal should cure that.

However, (and there’s always an IF…) my guess is that the rear axle is damaged due to lack of gear oil and that would mean a rebuild or replacement. Removal of the cover and a visual inspection would likely verify that the ring and pinion teeth are damaged; not to mention bearings which cannot be visually inspected.
Rebuilding a rear axle is highly technical and expensive so I’d say that the price quote is fair.

If the truck were mine what I would do is locate a used rear axle and change it out.
It would be cheaper and faster.
Rear axle prices vary depending upon the locale and salvage yard but around here a complete used rear axle can run about 300-400 dollars on the upper end of the range with many priced a lot lower. The last one I bought from a well-established and very reputable yard only set me back about 125 dollars and the yard even put a new pinion seal in it at no charge before loading it up for me.

Thank you! I do have a question about that. Would I be able to do it myself (not needing special tools) or would that still be best to take it to a shop with the used rear axle in hand to have them change it out? I’m sure if I did it at home, I could try to follow a video or something? Lol… Idk I mean if I have to spend the money for it I will. I just don’t want to if I don’t have to ya know?

Also, the cause of this happening that fast (all in a matter of like 2 hours) would be due to low oil? If so, most likely the gears are damage… Hmm I would of thought that there would of been a little bit better indicator if something was wrong. To let me know “how I need more oil” or whatever.

If it was just leaking fluid I’d say replacing the pinion seal for $150 would fix it. But the fact that you heard noise (quite loud) and feel a vibration on acceleration tells me that the ring and pinion is done for. That spells a complete differential overhaul. $1500 is optimistic. But I would never give you an estimate that I would stand by without seeing the truck in person.

The last one I bought from a well-established and very reputable yard only set me back about 125 dollars

Not too long ago my neighbors 2006 F150 needed a diff overhaul. The bolts holding the ring gear to the carrier had come loose, ate up everything in there. $2200, and parts were less from the Ford dealer than anyone else. He suggested a used install, I sent him looking, best price for a good used diff we could find was $600. Rather than take a chance on a used we fixed his with new parts.

@asemaster … I would just ask salvage yards for any used differentials for an 07 f150?

Yes, but you’re going to have to know the gear ratio of your current differential. It’s going to be something like 3.55 or 3.73 or 4.11. You may find that on a tag or stamped into the axle tube housing, or you may need to have the truck on a hoist to calculate it.

Thank you!. I definitely wouldn’t of known that. Haha

As I said, rebuilding a differential is very technical and is far more complex than just throwing another gearset in there. If you did that the end result would be a catastrophe.

If you call a salvage just ask for a rear axle assembly. There are some salvage yards that will install what they sell for a nominal fee although this type of yard is not common.

About 20 years ago a local farmer was carping about the 1700 dollar price tag of a ring/pinion set (gearset only) for his Case tractor.
When I asked if he checked pinion preload, backlash, etc he had no clue what I was talking about and brushed aside my comments about trouble in the future.
Luckily for him and due to the slow speed nature of tractors it actually held up for a few years before giving up again. He now drives another tractor…

Hahah, yeah I wouldn’t brush aside the comments you made… But I sure would look at you like a dog tilts its head at something funny or confusing. Lol I have no idea what any of that is!

Take ok4450’s comments seriously. The percentage of mechanics who know how to rebuild differentials today is far smaller than it was years ago.

If you’re going to rebuild it yourself, be sure to take the time to learn how to do it correctly. Else you’ll be right back in there.

I have experienced exactly the same failure on my truck. The noise tells me you have failed the pinion bearings. It may require only new bearings so then $1500 would be about right, OR it may need a new ring and pinion adding about $500 to the bill. Or those bearings may have destroyed the axle housing itself requiring a used axle anyway. And @ok4450 is dead-on, finding someone who can rebuild an axle these days is tough.

Your cheapest play is to buy on from a local wrecking yard. On www.car-parts.com, a used part finding site, they are running $1000 to about $1500 no matter which axle you have. A rebuilders website, www.powertrainproducts.net, is showing prices about $1400.

Swapping out the rear end with a good used one is a reasonable DIY driveway job while rebuilding the old carrier is a challenge for professional mechanics.

I would suggest pulling the rear cover to inspect for damage and if there are any broken parts or chips or when spinning a wheel there is indication of something broken call the local junk yards. It might surprise you how easy it is to swap the axle out.

I’d also probably be looking for a used replacement & I agree swapping the whole thing out isn’t too bad of a DIY job for someone with some mechanical ability . Bearings & gears go south fast when dry of lubricant .

Agree with the 2 comments above. Swapping a rear end is a reasonable DIY job but get a friend to help, rears are heavy and cumbersome. It helps to have an impact wrench as the bolts get rusty, may help to have line wrenches for the brake lines, too. A big breaker bar and an extender pipe for extra ooompf helps, too.

A few words of caution about swapping out a rear end . . .

Use new u-bolts and nuts

Do a fluid drain and refill with the correct viscosity fluid, especially if it’s limited slip. This will most likely mean removing the rear cover. I don’t think F150 has a drain plug . . . ?

Remove the rear rotors and take a good look at condition of the parking brake shoes and axle shaft seals

I like Ok’s idea to just swap out the innards from a junkyard unit. Those Ford truck differentials are pretty tough, rarely fail unless they run out of gear oil. No need to replace the case parts or the axel unless an inspection while removing the innards proves otherwise. You might need some machining done on the axel shafts though, if they got torn up in the process.

I’m just a driveway diy’er, own a Ford truck – a 40 + year old one with a Dana 9 incher. All by myself I put it on jack stands and removed the two axel shafts and the third member one time in my driveway. It wasn’t really that difficult. At least not as difficult as I thought it would be. I did have a detailed manual on hand showing how to do it.

Removing it – like I say – wasn’t overly difficult. Getting it back in by myself was something of a magic trick. It is heavy and slippery. I came close to dropping it on my noggin a couple of times. I’d get some help for that part at least, if you are thinking of doing this yourself.

Do you really want to do this yourself? Think on that a bit. Auto mechanics are trained how to do this, have the experience to do it, and the right tools and equipment.

If you are still “go for doing it myself”, as you might expect, this is a big job and requires a certain amount of upper body strength to do safely.

I personally do not like the idea of swapping out the innards with those of a junkyard unit

It’s clear from the pictures that this axle does not have a drop-in 3rd member. We have a few F150s of OP’s vintage in our fleet, so I do know a little bit about this situation. So that rules out a driveway “quickie”

If it did, swapping out the 3rd member would be relatively easy, but as I said, that is not the case here. No pun intended :wink:

Swapping/replacing parts in this situation will be labor-intensive. The big questions are who’s doing the work, and who’s paying for the labor?

Best to either replace the complete axle with a good used part, provided the price is fairly low, the used part actually is good, and OP supplies the free labor

Or pay a shop to repair the differential, presumably with many new parts and the correct adjustments. If going for this option, I think it best to bring the whole truck to the shop, not just the rear end

I believe OK4450’s suggestion was to swap out the entire rear axle and to not try just replacing the innards. Swapping the innards is not a job for other than a pro with the knowledge and tools to do the job properly. It ain’t as simple as it looks. Not even close.

If it were me, and I was 25 again, I’d follow the advice already given.