i still have this problem and it will drives me nuts....
2001 E350 7.3L PSD converted to 4X4 with an `06 F250 front wit 34" tires.
Here's the problem: With my foot on the brakes and at a full stop, the steering is very hard to turn. Like it's binding up or something.
When the brake pedal is released the power comes back to the steering. It is because than the tires than can roll on the street a bit....i think.
First I said it was the pump of course. Replaced the pump....same problem. This only occurs when the brake is applied firmly and sitting still. Everything is fine when the truck is in motion. No brake or steering problem at all.
I checked all bearings and links several time. If i lift the front i can move from left to right just pushing the tires with my hands, so nothing goes hard there.
Van has an vacuum pump for the brake and a hydraulic for the steering.
Can anyone advise me on this issue?
All comments and ideas are welcome. I am near to buy a new steering gear but thats a lot of money just for a "test"

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www.Dieda-unterwegs.net
2001 SMB E350 4x4 7.3 Powerstroke
1968 Pontiac Firebird 400 Convertible ,1978 Peugeot 504 Convertible,1988 Porsche 911 Carrera 3.2,KTM 300 EXC,BMW G/S Paris Dakar,BMW "Diabolo"

If no one speaks up, try posting this on the Ford Truck Enthusiast forums. I have heard of it and think it is a fairly common problem. I don't want to say for sure but I think it might be your brake vacuum booster.

Good luck!

Thanks Scotty,

Still did post it there will see if i get input from them. I do not think it is Brake vacuum booster. It has nothing to do with the steering system as it is not an combinated system....

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www.Dieda-unterwegs.net
2001 SMB E350 4x4 7.3 Powerstroke
1968 Pontiac Firebird 400 Convertible ,1978 Peugeot 504 Convertible,1988 Porsche 911 Carrera 3.2,KTM 300 EXC,BMW G/S Paris Dakar,BMW "Diabolo"

Do you have wheels with extra offset?

If so, the tires may need to roll forward/back when turning from a dead stop. The brakes stop that little bit of rolling and bind up the steering. Try it on sand or grass and see if it is easier.

Or, turn the wheel full lock, mark the top of the tire, turn full lock the other direction and see if the tire has rotated slightly. Do that with the parking brake on so you know the van didn;t move.

Mike

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Alaska to Key West, Labrador and more
Prostate cancer survivor. See Thread Prostate cancer and Sportsmobiles
2015 VW GTI 2020 Fiat 124 Spider
2012 E250 Hitop camper

I think thats exact the problem ....but my wheels have 0 offset and i have no spacers in. So i think normaly the power steering should have enough power to get it.
I forgot to say that it does NOT help if i rise up the rpm´s....if i get my feed from the brake i am able to turn. Still harder than usual but it works.
I can not imagine that this is normal

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www.Dieda-unterwegs.net
2001 SMB E350 4x4 7.3 Powerstroke
1968 Pontiac Firebird 400 Convertible ,1978 Peugeot 504 Convertible,1988 Porsche 911 Carrera 3.2,KTM 300 EXC,BMW G/S Paris Dakar,BMW "Diabolo"

Since our vacuum pumps are driven off the serpentine belt, higher rpm should mean more vacuum if the pump is working properly. Since your brakes are working properly, I assume that the vacuum pump is working properly. How about connection between vacuum pump and assuming there is one the brake assist cannister does it also attach to the steering pump? (I had a Volvo P220 which had the brake assist cannister go out and my front brakes seized...) Obviously more vacuum must be required to assist steering with the more tire resistence while the wheels are not turning and the vehicle stopped.

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2002 E350 ext.; 160K; 7.3L; 4R100 (w/4x4 deep pan & filter); 4x4 conv. w/2007 F250/F350 coil frnt axle (oppos. dual Bilstein press. shocks cured DW) diff chg from 3.55 to 3.73 (bad!); BW1356 t.c. (bad!); LT265/70R17/E Michelin LTX M/S2; Engel MT60 Combi Fridge-Freezer; 4 BP 380J pv panels; Auragen 5kw AC gen. in top alt. position; Webasto Dual-Top; Voyager top. 1995 5.8L EB Bronco, bone stock.

sorry did not get it...
i have an 7.3 there the steering is not assist from vacuum. It is assist from power steering pump which is hydraulic and driven from the serpentine belt.

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www.Dieda-unterwegs.net
2001 SMB E350 4x4 7.3 Powerstroke
1968 Pontiac Firebird 400 Convertible ,1978 Peugeot 504 Convertible,1988 Porsche 911 Carrera 3.2,KTM 300 EXC,BMW G/S Paris Dakar,BMW "Diabolo"

It might be normal. Since Ford didn't make the van 4wd, it may be the unique combination of parts that causes this.

Can't say I've ever tried to turn the wheels while standing on the brakes. I will try that next time I use the van - if I remember.

Does your van have an SMB 4x4? Or Quigley? Or other? My van has an F350 front axle and F350 wheels. Your wheels look like F350 wheels, what is the axle? Dyna or F350 or?

Mike

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Alaska to Key West, Labrador and more
Prostate cancer survivor. See Thread Prostate cancer and Sportsmobiles
2015 VW GTI 2020 Fiat 124 Spider
2012 E250 Hitop camper

What he said ^^. I can't test your problem with my van, but I would not be surprised if this sympton is normal for 4x4 vans. 4x4 F-350's apparently have the hydroassist steering. And probably just for this reason.* Since our vehicles start out as 2WD with relatively small tires, it is possible that it is merely a result of adding the additional resistance of the added-on 4x4 front axle and added tires which are larger than the oem stock van tires. BTW, my 17" wheels have larger than stock offsets. So is it true that a wheel offset means more scuff when turning the wheel when stopped? I am trying to visualize the contact patch and the action of the tie rod turning the wheel. I guess that the offset constitutes a lever acting on the balljoint putting additional resistence against the turning force applied by the tie rod?

* And apparently they can still have this problem even with the hydroassist:

http://www.ford-trucks.com/forums/80812 ... ering.html

I have "Learning slowly..." as my avatar caption on ford-trucks.com for a reason...

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2002 E350 ext.; 160K; 7.3L; 4R100 (w/4x4 deep pan & filter); 4x4 conv. w/2007 F250/F350 coil frnt axle (oppos. dual Bilstein press. shocks cured DW) diff chg from 3.55 to 3.73 (bad!); BW1356 t.c. (bad!); LT265/70R17/E Michelin LTX M/S2; Engel MT60 Combi Fridge-Freezer; 4 BP 380J pv panels; Auragen 5kw AC gen. in top alt. position; Webasto Dual-Top; Voyager top. 1995 5.8L EB Bronco, bone stock.

The steering pump has a pressure relieve valve to prevent damage to the steering components if you are at full lock or against a curb. This is why raising RPMs does not increase steering boost. The system was simply designed for a smaller tire. I am not sure if anyone makes a higher pressure valve. There may be some liability associated with that upgrade because it could require higher rated hoses all around.

That said.... Why would you do this? I've always been taught since say one of driving not so turn the wheels while at a full stop. I alway roll, even ever so slightly. I had to train some of my driver's not to do it because the front tires on our trucks were getting worn out in 20,000 miles (and 19.5's aren't cheap). The tie rods probably would have gotten worn out too if it weren't the the annual Dodge tie-rod recalls (and recalls for the recalls).

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2000 E450 dually V10 wagon