The power steering on my truck stopped working. I thought it was the power steering box because I put in a new power steering pump last summer. My truck has steered hard at a low speeds forever. I decided to upgrade to a 2011+ steering gear box.
I started with these threads.
http://powerstrokearmy.com/forums/showthread.php?t=75000
http://powerstrokearmy.com/forums/showthread.php?t=77149
This is what I learned.
1) There was an upgrade to the Superduty 250 and 350 steering boxes in 2011. The 2011 box is much larger. Ford replacement Superduty boxes are very expensive. I got a good used box from a wrecker.
F450 and 550s use a completely different steering box. It is much larger than any F350 box.
2) The 2011 steering box bolt pattern is identical to the 2008. However, the bolts are different. The 2008 box uses M14 x 120mm. The 2011 box uses M16 x 120mm. The bolts are supposed to be replaced when the box is replaced. Ford sells them for about $5 each. They have blue thread locker on them.
The part number for the bolts for my box was W713909S439.
One dealer told me that the 2011 boxes use 18mm bolts. The dealer part listing has the size listed. I suspect he was looking at a F450/550 box, but who knows. Double check before using my part number.
I did not have to enlarge the holes in the 2008 frame to use the M16 bolts. But it is pretty tight getting them to line up.
3) The steering input shaft is different on the 2011 box. The 2008 box has a splined input shaft. The 2011 input shaft has 3 lobes. The lower half of the steering shaft is interchangeable between the 2008 and the 2011. If you get a 2011 box from a wrecker, get the lower steering shaft that mates to it and swap it with the 2008 shaft in the truck.
4) The oil ports are the same on the 2011 box, but the are in a slightly different location.
The pressure port is closer to the engine. I had to bend the line just a little bit to clear the EGR cooler and make it fit. Bend gently and a little bit everywhere so not to kink it.
The return line is a little closer to the firewall. I had to loosen the clips that hold the return line to the facia by the oil cooler and under the bumper so that I could get another inch of travel. It also needed to be bent just slightly.
5) The 2008 oil fittings work with the 2011 box. The fittings are fairly easily accessible with an 18mm open end on the 2008. The fittings are really difficult to tighten on the 2011 box due to clearance issues with lines. I had to cut an 18mm wrench down in order to fit without interfering with the lines.
I used a cheater wrench on the cut off wrench to get the fittings tight. I inspected the O Rings on my fittings and found them to be good and reused them. Nothing leaks.
6) The 2011 box is fairly heavy and bulky. It takes a bit to get it in place and get the bolts started.
7) The 2011 pitman is the same as the 2008 pitman. I didn't remove the pitman on my 2011 box. However, my steering wheel is now not straight. I'll try to adjust the drag link to make it straight. The lower steering shaft is keyed where is mates to the upper steering shaft and the the power steering box. There is no way to adjust the steering wheel other than on the pitman or the drag link.
Other than these issues swapping the box was straight forward.
Here are the steps to swapping the box.
1) Jack up the drivers side front wheel, put it on a jackstand. Remove the wheel.
2) Remove the fender liner.
2b) Unclip the ABS connector and move it out of the way.
3) Slide the plastic flex linkage guard up and out of way.
4) Remove the input shaft locking bolt (13mm ?)
5) Remove the drag link from the pitman arm. A big pickle fork works well. The nut is 24mm.
6) Suction out the oil reservoir.
7) Remove the oil lines. 18mm wrench.
8) Remove the 3 bolts holding the box. 17mm on the 2008, 21mm on the 2011 bolts.
9) Remove the box.
When you put the new box in place, make sure the oil lines are above the box as well as the lower steering shaft.
Use heavy duty screwdrivers or line up bars to align the box while you get a bolt started. It is heavy.
It turns out that my steering box was OK. My power steering pump failed.
The 2008s have had issues with poor steering boxes.
https://www.edmunds.com/car-news/fe...0-super-duty-trucks-for-steering-problem.html
Symptoms were
- no power assist at all at idle. Impossible to dry steer the tires.
- no power assist when the engine was revved up. Still impossible to dry steer.
- hydroboost brake system worked fine, no extra foot force to stop
The manual says that if the pump is bad, steering will return when you rev up the engine. And if there is no pressure from the pump, the brakes will be affected.
This was not the case on my truck. Steering didn't return and the brakes were good. Thus I thought my pump was fine.
Here is a better test... jack up both front wheels and turn the steering wheel to the lock in each direction. If the pump is good, you'll hear the pump strain and the motor pull down when you reach the steering locks. My engine doesn't pull down at all. And there is no straining from the pump.
Also, with the wheels off the ground it is easier to turn them lock to lock with the engine revved up to 2500. It shouldn't make any difference when the wheels are elevated.
I started with these threads.
http://powerstrokearmy.com/forums/showthread.php?t=75000
http://powerstrokearmy.com/forums/showthread.php?t=77149
This is what I learned.
1) There was an upgrade to the Superduty 250 and 350 steering boxes in 2011. The 2011 box is much larger. Ford replacement Superduty boxes are very expensive. I got a good used box from a wrecker.
F450 and 550s use a completely different steering box. It is much larger than any F350 box.
2) The 2011 steering box bolt pattern is identical to the 2008. However, the bolts are different. The 2008 box uses M14 x 120mm. The 2011 box uses M16 x 120mm. The bolts are supposed to be replaced when the box is replaced. Ford sells them for about $5 each. They have blue thread locker on them.
The part number for the bolts for my box was W713909S439.
One dealer told me that the 2011 boxes use 18mm bolts. The dealer part listing has the size listed. I suspect he was looking at a F450/550 box, but who knows. Double check before using my part number.
I did not have to enlarge the holes in the 2008 frame to use the M16 bolts. But it is pretty tight getting them to line up.
3) The steering input shaft is different on the 2011 box. The 2008 box has a splined input shaft. The 2011 input shaft has 3 lobes. The lower half of the steering shaft is interchangeable between the 2008 and the 2011. If you get a 2011 box from a wrecker, get the lower steering shaft that mates to it and swap it with the 2008 shaft in the truck.
4) The oil ports are the same on the 2011 box, but the are in a slightly different location.
The pressure port is closer to the engine. I had to bend the line just a little bit to clear the EGR cooler and make it fit. Bend gently and a little bit everywhere so not to kink it.
The return line is a little closer to the firewall. I had to loosen the clips that hold the return line to the facia by the oil cooler and under the bumper so that I could get another inch of travel. It also needed to be bent just slightly.
5) The 2008 oil fittings work with the 2011 box. The fittings are fairly easily accessible with an 18mm open end on the 2008. The fittings are really difficult to tighten on the 2011 box due to clearance issues with lines. I had to cut an 18mm wrench down in order to fit without interfering with the lines.
I used a cheater wrench on the cut off wrench to get the fittings tight. I inspected the O Rings on my fittings and found them to be good and reused them. Nothing leaks.
6) The 2011 box is fairly heavy and bulky. It takes a bit to get it in place and get the bolts started.
7) The 2011 pitman is the same as the 2008 pitman. I didn't remove the pitman on my 2011 box. However, my steering wheel is now not straight. I'll try to adjust the drag link to make it straight. The lower steering shaft is keyed where is mates to the upper steering shaft and the the power steering box. There is no way to adjust the steering wheel other than on the pitman or the drag link.
Other than these issues swapping the box was straight forward.
Here are the steps to swapping the box.
1) Jack up the drivers side front wheel, put it on a jackstand. Remove the wheel.
2) Remove the fender liner.
2b) Unclip the ABS connector and move it out of the way.
3) Slide the plastic flex linkage guard up and out of way.
4) Remove the input shaft locking bolt (13mm ?)
5) Remove the drag link from the pitman arm. A big pickle fork works well. The nut is 24mm.
6) Suction out the oil reservoir.
7) Remove the oil lines. 18mm wrench.
8) Remove the 3 bolts holding the box. 17mm on the 2008, 21mm on the 2011 bolts.
9) Remove the box.
When you put the new box in place, make sure the oil lines are above the box as well as the lower steering shaft.
Use heavy duty screwdrivers or line up bars to align the box while you get a bolt started. It is heavy.
It turns out that my steering box was OK. My power steering pump failed.
The 2008s have had issues with poor steering boxes.
https://www.edmunds.com/car-news/fe...0-super-duty-trucks-for-steering-problem.html
Symptoms were
- no power assist at all at idle. Impossible to dry steer the tires.
- no power assist when the engine was revved up. Still impossible to dry steer.
- hydroboost brake system worked fine, no extra foot force to stop
The manual says that if the pump is bad, steering will return when you rev up the engine. And if there is no pressure from the pump, the brakes will be affected.
This was not the case on my truck. Steering didn't return and the brakes were good. Thus I thought my pump was fine.
Here is a better test... jack up both front wheels and turn the steering wheel to the lock in each direction. If the pump is good, you'll hear the pump strain and the motor pull down when you reach the steering locks. My engine doesn't pull down at all. And there is no straining from the pump.
Also, with the wheels off the ground it is easier to turn them lock to lock with the engine revved up to 2500. It shouldn't make any difference when the wheels are elevated.
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