Where do you jack up your Expedition?

good answer from someone that gets caught in a lie

and another lie.

why would you reply to something you didn't read

I am 58

Started working professionally on cars when I was 18 as a certified master state of Michigan mechanic working at independent repair shops. At around 30 I had my own foreign car repair shop for 4 years, then I spent a few years bouncing around Ford and Honda dealers. Then I got a job at Ford in the X garage building prototype vehicles, worked my way up to group leader, then vehicle instrumentation coordinator worked at the Pilot Plant, there for 13 years until Ford downsized and laid the whole department off.

Then I worked at TRW Automotive for 6 years doing brake and suspension development until the next automotive bust, then at American Axle, then at McLaren engines, and finally to where I am not that I am not going to disclose.

My point telling you all this is I am not just some dumb shit spewing nonsense. I know what I am taking about as far as this stuff goes.


Sometimes people just need to shut up and listen and stop arguing about shit they know nothing about.

Big Brian said:

if you "theory" was true the highways and byways of this country would be strewn with vehicles with bent axles all over the side of the road

oh deary me

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A high school buddy had one. He was sitting there one day parked, and his axle sheared off in two or snapped or something.

I think that thing was called a.... TOY-ota.


PS the idgit constantly imbibing and then repeatedly whacking that pos into various obstacles probably didn't help matters either, and I'm fairly certain it was a salvage title to begin with....then again, I'm also certain THAT drunken oaf could accidentally break just about anything.

Just replaced a rear axle in my 98 expy and had it jacked up by the differential.....had it up to 75 on m24 yesterday and no shudder or rear end blown apart....take your lumps, eat your crow and get your truck fixed already

People have been jacking on the diff housing for ages, and they have been doing it "wrong", "lazy", "easy", "simple" for ages that way too. It is a "lawyers" sentence, but not only because of the safety in jacking. (It is considered sufficiently safe to jack any vehicle with two tires down, but three tires is obviously safer.) The second reason the attorneys say not to jack using the differential is because they really do break sometimes because of it. And Ford does not want to pay for new differentials under warranty, or trying to fix malfunctioning ones from pumpkin shell deformation because rear end lifting that way.

If you really look at it, its a lot of weight on the front to back edge of the shell, right at the cover location. And the cover itself is NOT a rigid structure providing support to the pumkin shell for several reasons. First the cover is not very strong, its stamped steel or aluminum that is not structurally strong. Second its just bolted on, and not tightly. e.g. There is a gasket there (paper or silicone) that is DESIGNED to give (in order to be maleable to do its actual job, stopping leaks out of the cover / pumbin join. Its is not a structure support element. This means the pumbkin can flex, and gets very little support out of the cover.

95% of the time, if it flexes, it flexes back (at least enough) so that you don't have any ill effects. But 0.001-5% of the time, the flexing does not entirely recover, and it adds up. So lift that way over a long period of time, over 10-20 years, you might end up with a problem. Ford does not want to pay for even one unit in the warranted 3 years, or sometimes 7 for powertrain, so they void the warranty if the diff fails, and they can prove you lifted it that way. Dealers don't (usually) lift them that way, they have lifts. But plenty of even certified mechanics do it that way because its convenient. If it fails, they will just lie and its the customer's problem.

The wording is designed to head off the small number of failures (but perhaps 1%) from home mechanics not smart enough to lie, and who then say, "it doesn't say "don't do that" in the manual. Well, it does say don't do that in the manual, so that Ford will win that battle.....

If you break it, its an expensive repair or replace. So, I just jack on the axle about 2/3 of the way out to the tire. 1/3 to the tire, 2/3 to the differential. And then the other side. The closer the jack stands are to the tires, the more stable the lift, but the most stress on the tube. The closer to the diff, the least stress on the tubes, but the least stability in the vehicle on stands. Also the closer to the tires, the less incline there is during the second lift, and thus the least sideways vehicle movement as you tilt the vehicle up on the jack the second time (and are resting on one stand, tilted above the stand.) I like about 2/3 out (e.g. 1/3 point nearest the tires.)

These days, I just use a T-bar ($55 bucks Harbor Freight) and lift the back via the two axle tubes simultaneously, near the diff, on either side. Then I slide in jack stands at the 2/3 out mark (1/3 near the tires) on each axle, and lower as carefully and gently as I can onto the stands.

Though 98% of the time, you can lift just fine using the diff pumpkin shell, do you really want to be that 2% of the failures? Its all on you then, as Ford definitely will not pay for it, and that is the REAL reason for the language in the owner's manual. TO cover the 2% of the time when the shell bends too much, or cracks. With that language, its NOT on Ford, its on you. Their (Ford's) problem is solved, and yours have just begun.

MesaGuy said:

I just use a T-bar ($55 bucks Harbor Freight) and lift the back via the two axle tubes simultaneously, near the diff, on either side.

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What's a T-Bar?

Nice analysis, by the way!

Jack anywhere on the frame if it isn't rusted to ****

That's the beauty of frame trucks

@Trailmaster. The "T-Bar" (my slang) is the accessory jack replacement crossbeam saddle available on many a jack, from many a vendor. Amazon sells them, as do most racing supply stores (search jack crossbeam). I just found a great deal on a American, Foundry and Furnace (AFF, USA made) crossbeam that drops onto any 1 1/8 inch saddle jack. e.g., the "hole" (e.g. saddle stud size is 1 1/8 inch). That deal was at JBTool. The Daytona and Pittsburgh 3 ton and 4 ton jacks at HFT can take a crossbeam from only from HFT. (The Daytona crossbeam, but it only works on the HFT jacks, and the reverse, those jacks need THAT Daytona crossbeam). A reasonable number of people call these things "T-bars" 'cause the whole jack assembly is sort of shaped like a T when the crossbeam saddle is on your jack.

If you get the "right" crossbeam, that has enough vertical lift pad adjustment, and then set the jack crossbeam at minimum width (usually about 24-28 inches) then you can straddle the Differential case (pumpkin) and lift using the two axle tubes. Then lift it up, drop in some jack stands, lower it down. Same as jacking from the diff case (pumpkin) but without the risk of actually warping or cracking the case. And if I wasn't clear before, that risk is pretty low. The cases are pretty stout, but they are not indestructible. They do not get support from the cover, and depending on the shape of the case, they can put all the pressure on a small area (about 1 inch wide, by 1/4 inch wide, right at the case edge (where it meets the cover)).

They get jacked that way all the time. But they do occasionally crack, or warp.... Ford protects itself by saying "don't do that." Dealerships (and most mechanics) protect themselves by having mechanics that will claim it was never jacked that way when it fails jacking that way.... All on the owner, 'cause how you gonna prove it.

I'm just careful is all. For $55 bucks, I got an attachment for HFT jack, and for $100-$150 an attachment for any 1 1/8 inch saddle stud/ring jack, and then I don't have to worry about it. Plus occasionally, the crossbeam accessory is useful for jacking the front of a front-wheel-drive vehicle under the wishbone suspension arms. Those smaller SUV and cars are uni-body, and don't always have nice cross members like the Expeditions do up front. The Expy's are obviously easy to jack up at the front at vehicle via the cross member without needing a crossbeam.

Some examples:

and0r said:

The differential is a precision component, with extremely tight tolerances and is more difficult to rebuild than a Ford automatic transmission! Putting all the trucks weight on a very small area directly on the differential seems like a very bad idea. Many people do this and it's accepted practice for DIY mechanics. But I do believe you are flexing the steel by just a millimeter or two or three, and this definitely something you wish to avoid.

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Have you ever actually opened up a differential?

Yes, it's a precision component, but the most important "precision" part of that is the backlash, or the distance between the teeth in ring gear and pinion. This is generally set using shims (and/or, in some cases, screw/bolt adjusters) to physically locate the entire entire carrier assembly (and thus the ring gear, which is directly attached to it with multiple bolts) in a horizontal direction. The three openings into the housing are one each for the two axle shafts and the last for the pinion gear. All three are generally structurally reinforced with multiple gussets. The lowest/tallest thing inside the differential is the ring gear itself.

It would seem that you're proposing that adding stress to the lowest lowest point of the differential would crush the housing enough to either 1) physically impact the ring gear vertically, shifting its location on the carrier or 2) somehow crush both axle openings (and the steel tubes sticking right through them) while leaving the pinion nose fully intact, and somehow deform/destroy one or more of the shims locating the carrier assembly, thus allowing the entire floating assembly to dislocate in relation to the pinion gear. If you're proposing #1, I can assure you that every differential I've ever seen has enough clearance so as to not contact the ring gear because of it (even if it was a millimeter or two, which it isn't, but we'll get to that). If you're proposing #2, it's evident that you've never actually worked on/in a differential ever and are mystified as to the actual internals that make up this "precision" component.

If you've ever worked on a differential, you should at least be familiar with a differential spreader. Its sole purpose is to deform the differential. Except it applies force horizontally to widen out the differential and allow for easier removal of the assembly. Even in this direction, where the physical tube openings and associated gussets aren't lending any structural support and you don't have a cover providing even more structural rigidity, the force required to deflect the case a tiny fraction of an inch is relatively massive; and then it bounces right back once you remove the spreader. So no, a bit of force in the substantially-more-reinforced vertical direction is not going to subtly warp the housing "a millimeter or two", it'll be a tiny fraction of a fraction.

Just about the worst thing that could happen from jacking up by the differential is the very slight break in the sealing surface/gasket that results in a slow leak. And I've never seen that happen either. Not in my couple decades of wrenching, and not in the dozen or so years I've been bashing/dragging Jeep differentials on rocks off road.