Oh man, there are many threads less than 10 years old to bump. haha

 

 

Posts 4 and 8 are the useful ones.

 

 

Use a floor jack, keep it off the diff cover (as already mentioned ~10 years ago)

 

Back in the day, 1976 to be exact, I had a 1967 Chevrolet 1/2 ton pick up I regularly overloaded with cement, concrete block, sand, gravel and rock as we landscaped around our first home. The 250 cu. in. Chevy 3 speed stick could haul a full bed-load of rock, which the Monrovia pit operator was happy to load for $10. As he dropped the rock into the bed, I'd watch the truck sag on its springs until the axle contacted the bump stops. It was only a couple of miles from the pit to my house on surface streets. One morning before I headed out, I noticed a large wet spot under the truck. Inspection revealed the axle carrier had cracked at the tube and had pretty much drained itself. Turns out that 6' bed load of rock weighed close to 4000 lbs. That is the reason I asked about jacking under the center of the differential of my F 150 after reading the caution in the owner manual.

 

Yup, i was asking all the same questions when i got my old Ranger, seems every shop in existence does it, and when i asked a friendly shop, they said no issues. Everything suggests it's something that catches the diff cover edge that would cause an issue.

Factory jack/lift points are the middle of the axle tube, one side attaches to the wheel/hub and the other attaches to the diff - technically if you lift by the diff, it's only supported by the axles, so it does strain it, i imagine if the bed is full, it would push down heavily on the other side (non diff side) of the axle tubes.


Remember, weight comes to the rear axle through the hubs/suspension linkages, the diff is technically the weakest point along the axle to take weight as it's not supported anywhere else.

 

I am guilty of jacking rear axles by pumpkin in the past, (for convenience). Never caused a problem doing that either.

Nowadays, being retired, the extra time to jack twice to put the rear axle on jack stands is mote, so I do it.

Think all a person risks is a leaking rear diff. Go for it should you choose.

 

I have done this many times, that being said, one of the reasons the manual says not to do it is the axle tubes are little more than spot welded into the differential housing. Lifting by the housing can, though I have only seen it once, cause the axle tube to loosen. If you notice, there are two weld holes on each side, one in front and one in back, where the tube is inserted into the housing. It is press fit and then welded in those two holes on each side. They are pretty strong but still, lifting a 6000lb truck by the center of the pumpkin puts stress on those welds. And before you tell me I don’t know what I am talking about, I was a Certified Master Technician for 30 years.

 

Proper way is jack up each side separately from the axel tubes.