2011 F350 hydroboost issues, only steers when rev motor

[makemeknowit]

Not my truck. Friend snagged it at an auction. Says he replaced pump and hb. I don't shit about hb but thought I'd see what I could dig up. What say ibb?

 

[Clb]

Air in system
Yes it's a thing with h.b.
Also what pump is being used....

 

[Tiha]

Maybe a seized ball joint, or even u-joint on axle shaft?

There was a point on the earlier superduties where ball joints being too tight was an issue. There was a whole process about dropping the tie rod out and putting a torque wrench on the knuckle to see how much effort it took to turn the wheel with the tires on the ground.

 

[arse_sidewards]

There was a point on the earlier superduties where ball joints being too tight was an issue. There was a whole process about dropping the tie rod out and putting a torque wrench on the knuckle to see how much effort it took to turn the wheel with the tires on the ground.

Fuck that Jimmy Numbers shit. Just jack the truck up and steer with the engine off. If it feels normal for a vehicle with the tires in the air then nothing in the steering is tight enough to be the problem he's chasing.

 

[Tiha]

Fuck that Jimmy Numbers shit. Just jack the truck up and steer with the engine off. If it feels normal for a vehicle with the tires in the air then nothing in the steering is tight enough to be the problem he's chasing.

in the early 2000s superduties they had to be on the ground to act up. Jacking them up and taking the weight off everything operated perfectly.

Pretty sure there was a TSB.
Didn't find the TSB number but found the procedure.

The first few we did we used the low friction plates, but after doing a couple it was so obvious (with truck on the ground) that the plates were not needed. Just knock the tie rod out and put the torque wrench on it.

Again, this was for the 99-2010 superduties. Not sure it applies to the 2011.

SERVICE PROCEDURE
Verify stiff steering, wandering, or poor returnability after turns. Proceed as follows:
1.Check alignment and correct if not to specification.
NOTE:
USE 0.75 DEGREE OR LESS CASTER SLUGS TO CHANGE THE CROSS-CASTER. IF THE CASTER REQUIRES MORE THAN A 0.75 DEGREE CHANGE YOU MUST USE CASTER WEDGES THAT ARE INSERTED BETWEEN THE AXLE AND LEAF SPRINGS. USE IDENTICAL CASTER WEDGES ON BOTH SIDES TO CHANGE CASTER.
a.If alignment corrects the condition, return vehicle to customer.
b.If alignment does not resolve condition, continue to Step 2 (steering knuckle torque to turn test).
2.Perform the following steering knuckle torque to turn test:
a.Place vehicle on alignment rack with front wheels on low friction plates. Wheels must be pointing straight forward.
b.Remove tie rod from steering knuckle. Install a nut and bolt into the steering arm hole and tighten.
NOTE:
WHEELS MUST BE LOADED AND ON PROPERLY OPERATING TURN PLATES TO PROPERLY CHECK TURNING TORQUE.
c.Use a click-style torque wrench and position it on the bolt head so that the handle is pointing toward the front of the vehicle.
d.Set the wrench at 135 N-m (100 lb-ft).
e.Pull on the torque wrench so that you are turning the front wheel outboard.
1.If the knuckles turn without the wrench clicking, then ball joint turning torque is acceptable. Return vehicle to customer.
2.If the wrench clicks before the wheel breaks free and begins to turn, then the torque to turn the knuckle is too high. Continue by replacing ball joints (Step 3).
f.Perform this procedure on both front wheels.
3.If the torque wrench clicks before the wheel breaks free and begins to turn, then replace the lower ball joint with the greaseable Lower Ball Joint (1C3Z-3050-AB) and replace the upper with the current replacement part (F6TZ-3049-AA). Refer to the appropriate model/year Workshop Manual for removal and installation procedures.

There is also a gear mesh load check that a alignment shop can accomplish if this first procedure does not find the problem.

 

[arse_sidewards]

in the early 2000s superduties they had to be on the ground to act up. Jacking them up and taking the weight off everything operated perfectly.

Yeah I've had some FWD shitboxes that won't show a loose ball joint unless they're at ride height.

There is also a gear mesh load check that a alignment shop can accomplish if this first procedure does not find the problem.

Just the normal steps for checking/setting box preload or something more?

 

[Tiha]

Just the normal steps for checking/setting box preload or something more?

Honestly have no idea. Never got that far. It was always the ball joints.

Gear mesh problems I have ran into have always been too lose. Worn out boxes. You can adjust the preload, but of course if you over adjust you create other problems.
We usually just ordered new boxes at the first sign of wear.

In edit I will add, there was a period there that the replacements were just as bad as what we took out.
If you only needed the driver's side, you would only do the drivers side because there was a good chance the first set you put in are garbage. It was always a gamble. We have changed them 3 times before the truck was fixed and left the shop. You gotta test the new ones you were putting in the same way.
Have no idea what replacements are like now. This was 10-15 years ago.

 

[makemeknowit]

Went to his shop Saturday. I did 20 cycles, he had done some before I got there and he did some more after me. Steers fine with the fronts in the air UNTIL you press the brakes then it goes stiff unless you rev it up. Set it down and stiff again unless you rev it. What a fukin pain in the ass.

 

[holdmypocket]

Had a truck do something similar.. it turned out to be a leaking hose.. under higher load (turning 37’s thru an intersection) it would cut out and get hard to turn. Wheels in the air seemed fine

One day we were checking track bar mounts with the engine running and wheels on the ground.. turning the steering wheel back and forth a lot when someone noticed steering fluid shooting out from one of the hoses with each turn. Worth checking out maybe.