"[b:654c4848f0][i:654c4848f0]<font color="#6699ff">whose fixed this problem in the past?[/i:654c4848f0][/b:654c4848f0]</font>"
Take a look at the diagram below.
Note the left steering arm (Key 4), right steering arm (Key 15), adjustable end with cover (Key 28), tie rod tube (Key 31), and end with dust cover (Key 36).
Reviewed the [b:654c4848f0]SERVICE MANUAL JOHN DEERE 40 SERIES TRACTORS & CRAWLERS SM-2013[/b:654c4848f0] under the [i:654c4848f0]Toe-in Adjustment[/i:654c4848f0] topic on page 170-15-6.
"[b:654c4848f0][i:654c4848f0]Following disassembly of front axle or after replacing any of the steering linkage parts, check toe-in according to following procedure.
With front wheels in the straight ahead position, and the front of the tractor on the floor, measure front wheel tread width at front and rear of wheels at hub height. Proper toe-in is 1/8 to 1/2 inch less in front than in rear. To make necessary adjustment, loosen clamps at inner end of tie rods and set screws at outer ends. Turn each tie rod tube an equal amount until proper toe-in is obtained. Make sure set screws at end of tie rods are pointed away from the axle.
NOTE: Tie rods must be equal in length.
Turn steering wheel to extreme right and left. Steering arms must contact steering arm at each extreme.[/i:654c4848f0][/b:654c4848f0]"
Take a look at the photos below of the adjustable ends on "Audie" our Model 40S.
This is one method of centering the steering on the Model 40S and probably the Model 40U tractors.
Remove the adjustable tie rod ends from both the left and right steering arms.
Turn the steering wheel either to the extreme right or left.
Mark the top of the steering wheel with a small piece of duct tape.
Turn the steering wheel in the opposite direction, counting the number of revolutions, until it stops noting the position of the duct tape.
Divide the number of complete revolutions and any partial revolution by 2.
Turn the steering wheel in the opposite direction the new calculated number and "anchor" the steering wheel.
The steering wheel should be close to center.
Follow the directions above from the service manual.
Take a look at the diagram below.
Note the hex jam nut(Key 3), adjusting screw (Key 4), cover (Key 5), steering shaft (Key 8), and steering gear housing (Key 15).
Reviewed the [b:654c4848f0]SERVICE MANUAL JOHN DEERE 40 SERIES TRACTORS & CRAWLERS SM-2013[/b:654c4848f0] under the [i:654c4848f0]Adjusting Steering Gear Backlash[/i:654c4848f0] topic on page 170-5-5.
"[b:654c4848f0][i:654c4848f0]NOTE: Raise front end of tractor to remove load from front wheels.
Turn wheels so they are in the direct forward position. With adjusting screw lock nut loosened, turn adjusting screw in as far as possible and then back off several turns. Tighten screw until it just bears on steering lever. Tighten the lock nut.
Turn the steering wheel from right to left to check for bind. A slight drag should be felt when wheels pass center of straight ahead position.
When steering wheel is turned to extreme right or left, boss on upper spindle must contact stops on front end support. On adjustable front axle, stops on steering arms must contact stops on axle.
Fill the steering housing with quantity and weight of oil recommended in Section 30.
Replace grille and hood.[/i:654c4848f0][/b:654c4848f0]"
Take a look at the photo below.
Hope this helps.