Why can't you lift by differential?
05-17-2009, 03:03 PM
#13
6th Gear Member
Join Date: Feb 2007
Location: state of confusion
Posts: 7,635
You can make a 'jack adapter' that fits a circular plywood block into the cup and has a couple of blocks nailed to it that are spaced far enough apart for the pinch weld to fit between and tall enough to take the weight off the bottom edge of the pinch weld itself. Wood works just fine, although you'll most likely split a block from time to time like I did yesterday.
Norm
Norm
05-17-2009, 06:05 PM
#14
2nd Gear Member
Join Date: Nov 2008
Location: The Gump, Alabama
Posts: 240
These threads always end up like this...some say you can some say you can't, I've never personally but I've jacked up Ford trucks like this and never had the first problem. Who knows which is correct, I probably wouldn't on this car just because the manual says not to and I generally follow the advice of the folks who design/build stuff.
But along those same lines I bet FoMoCo wouldn't condone reflashing the computer with an aggressive tune or using a FI setup so use your own judgement...Good Luck with whatever you decide
But along those same lines I bet FoMoCo wouldn't condone reflashing the computer with an aggressive tune or using a FI setup so use your own judgement...Good Luck with whatever you decide
Last edited by solaratomic; 05-17-2009 at 06:08 PM.
05-17-2009, 06:49 PM
#15
6th Gear Member
Join Date: Sep 2006
Location: Gainesville, FL
Posts: 11,278
Guys, the axle just wasn't built to hold up the weight of the car from the diff. You don't have to know a lot about cars to see that. It's simple physics.
This is an over-simplification, but I'll try to illustrate it. Take a six foot long piece of rebar. This will stand in as our axle. Now put one end in a vice and try to twist it like a twizzler.
Not going to be very easy, is it? This is the kind of torque exerted on the axle when you're driving. It's got a lot of strength when it comes to that kind of force. That's what it's built for.
Now, as far as it holding up the car, let's get four cinder blocks to stand in for the weight of the car, and the wheels. spread two of the cinder blocks just under six feet apart and bridge the two with the rebar. This is is our wheel/axle set up. Then take the other two cinder blocks and put them on top of the bottom cinder blocks with the rebar between them. This is how the weight of the car is distributed normally.
Not much risk of the rebar bending is there? Now time to lift by the diff. Get rid of one of the bottom/wheel cinder blocks and put the other in the center to stand in for your jack.
How long before that rebar starts to bend?
The diff has a spot for a jack to hold up the weight of the axle while the car is on a lift or jack stands to work on the axle or suspension etc. It's not there to jack up and support the weight of the car. Now, you can tell me how you've been doing that for years now, and how your father did it, and his father before him. I'm just going to say, good luck.
I hope I made some kinda sense. I have my doubts.
This is an over-simplification, but I'll try to illustrate it. Take a six foot long piece of rebar. This will stand in as our axle. Now put one end in a vice and try to twist it like a twizzler.
Not going to be very easy, is it? This is the kind of torque exerted on the axle when you're driving. It's got a lot of strength when it comes to that kind of force. That's what it's built for.
Now, as far as it holding up the car, let's get four cinder blocks to stand in for the weight of the car, and the wheels. spread two of the cinder blocks just under six feet apart and bridge the two with the rebar. This is is our wheel/axle set up. Then take the other two cinder blocks and put them on top of the bottom cinder blocks with the rebar between them. This is how the weight of the car is distributed normally.
Not much risk of the rebar bending is there? Now time to lift by the diff. Get rid of one of the bottom/wheel cinder blocks and put the other in the center to stand in for your jack.
How long before that rebar starts to bend?
The diff has a spot for a jack to hold up the weight of the axle while the car is on a lift or jack stands to work on the axle or suspension etc. It's not there to jack up and support the weight of the car. Now, you can tell me how you've been doing that for years now, and how your father did it, and his father before him. I'm just going to say, good luck.
I hope I made some kinda sense. I have my doubts.
I would not hesitate to lift the rear at the differential, but I would only use it to lift, not support the car while under it. The main concern is the car swaying side to side and falling. It wouldn't take much movement to break your standard floor jack.
05-17-2009, 09:36 PM
#17
1st Gear Member
Join Date: Nov 2006
Location: Arkansas
Posts: 67
Ok
Well guy's I would love to see a rearend that has been twisted by jacking it up by the pumkin. I agree it is a short term to lift the car and then place jackstands or blocks under the tires. You can damage the diff cover if your not careful but bending the axle tubes because you lifting by the pumkin come on show me proof!!!!
Steve
Steve
05-17-2009, 10:22 PM
#18
Join Date: Aug 2008
Location: Missouri
Posts: 35
I always have, and I always will. In the offroad scene, pumpkins are dragged, smashed, and slammed into rocks constantly, and rarely do I hear about any damage besides rock rash being done to the pumpkin. 8.8's are included in those axles as well.
05-18-2009, 12:18 AM
#19
3rd Gear Member
Join Date: Sep 2008
Location: NY (Capital Region)
Posts: 581
Okay, I guess I don't get it. I haven't been a part of this forum for long, so I haven't been a participant in past threads on the subject, but it sounds like this debate has been going on a while now.
I just don't understand - The Ford engineers who designed the car tell us not to do something. Just by looking at it objectively, I can see why.
But then everyone wants to jump in and explain why you should do it anyway, even though it takes a minimum of effort and time more to do it the way the designers recommend.
What's Ford's stake in telling us not to do this? Do they have tiny little surveillance cameras hidden in our cars so they can watch every time we jack our cars up by anything other than the diff? They sit back and laugh, and call us names such as "sucker" or maybe "gulla-Bull", patting each other on the backs? They record the footage and play it back for all their friends, shouting things like "Ha! they could have been jacking their cars up by the diff this whole time! Instead they took the extra five minutes to jack it up at the pinch welds!"
I'm done with this thread. You guys have a good time.
I just don't understand - The Ford engineers who designed the car tell us not to do something. Just by looking at it objectively, I can see why.
But then everyone wants to jump in and explain why you should do it anyway, even though it takes a minimum of effort and time more to do it the way the designers recommend.
What's Ford's stake in telling us not to do this? Do they have tiny little surveillance cameras hidden in our cars so they can watch every time we jack our cars up by anything other than the diff? They sit back and laugh, and call us names such as "sucker" or maybe "gulla-Bull", patting each other on the backs? They record the footage and play it back for all their friends, shouting things like "Ha! they could have been jacking their cars up by the diff this whole time! Instead they took the extra five minutes to jack it up at the pinch welds!"
I'm done with this thread. You guys have a good time.
