PSP FOR INCREASING THE SERVICE LIFE OF POWER ANGLE TILT BULLDOZER COMPONENTS ON CERTAIN D5H TRACTORS - PS4299 - MAILED US AND CANADA, CACO, COFA, CFEL, COSA - REVISED 02/90 Caterpillar

July 22 1989
(Revised February 1990)
U-150
A-106
AU-103
E-66
O-92
6069, 6063, 6079  PS4299
NOTE: This Program can be administered either before or after a
failure. In either case the decision whether to apply the
Program is made by the dealer. When reporting the repair, use
"PS4299" as Part Number, "7755" as Group Number, and "96" as
Description Code.
NOTE: This Revised Service Letter replaces the July 22, 1989 Service
Letter. Changes have been made to the Parts Needed, Action
Required, and Service Claim Allowances.

July 31, 1991

Some components of the Power Angle Tilt Bulldozer may not have a satisfactory
service life on certain D5H Tractors. New components can be installed to
align the blade.

Model Identification Number Bulldozer Arrangement*
Identification Number
D5H 8RC1-1866*** 2AH1-1434
1DD1-741*** 1YH1-737
3MD1-697**
4KD1-505**
7NC1-601*** 2AH1-1434
1YD1-612**
2SD1-542**
9HC1-252**  1YH1-737
* Actual ending bulldozer arrangement identification number.
** Actual ending vehicle identification number.
*** Approximate ending vehicle identification number.

2 - 7J9351 Bearing-Sleeve
2 - 6D0217 Bearing-Sleeve
1 - 6Y4388 Bearing-Thrust
1 - 6Y4392 Pin-Pivot
1 - 4B4043 Bolt
1 - 4D3704 Washer
1 - 5B2079 Spacer
1 - 6Y0458 Retainer
1 - 3G8887 Collar
2 - 4T0088 Shim
2 - 4T0089 Shim
10 - 7X0453 Bolt
1 - 6Y0689 Pin (Rework until 8E2029 Pin As. becomes available)
2 - 6Y5763 Plate-Wear
2 - 6Y5765 Plate-Wear
1 - 9M1328 Bearing-Aligning
2 - 6Y5002 Spacer (or fabricate two of Spacer A)
1 - 6Y5863 Spacer (or fabricate Spacer C)
1 - 6Y5862 Spacer (or fabricate Spacer B)
1 - 6Y4389 Spacer (or fabricate Spacer D)
2 - 8G5258 Spacer2 - 7X0583 Washer
2 - 7X0346 Bolt
Note: Because of the limited availability of certain parts it will be
necessary to control distribution. If ordering difficulties are
encountered due to the
short supply, dealers within NACD should contact Technical
Services at 309-675-4373 or 309-675-4094. Dealers outside of
North America should contact their subsidiary office.

 FOR OPTIONAL REWORK
Modifying retainer of 2.0 inch singletree pin assembly
/
2 - 8G5258 Spacer /
2 - 7X0346 Bolt / Note: Listed on previous page.
2 - 7X0583 Washer /
/
Bulldozer Center Bracket
1 - 3G8932 Pin
1 - 4T0172 Trunnion
1 - 6Y4385 Sleeve
1 - 6Y4734 Bearing
C-Frame Hinge Pins
2 - 8G5243 Bearing
4 - 8K6276 Bearing
2 - 6Y4027 Pin

See the attached Rework Procedure, General Information, and Optional Rework
Procedure.

Product Caterpillar Dealer Suggested Customer Suggested
smu/age Parts Labor Hrs. Parts Labor Hrs. Parts Labor Hrs.
whichever (D/N) (Cost)  (C/L) (Sell)
comes
first
0-3000 100% 16 0 16 0 0
0-24 mo
3001-5000 33 1/3% 8 0 8 50% 16
25-36 mo
NOTE: This is a 32-hour job.
Product Caterpillar Dealer Suggested Customer Suggested
smu/age Parts Labor Hrs. Parts Labor Hrs. Parts Labor Hrs.
whichever (D/N) (Cost)  (C/L) (Sell)
comes
first
ALLOWANCES FOR OPTIONAL REWORK
Modifying Retainer Of 2.0 Inch Singletree Pin Assembly
0-3000 100% 1 0 0 0 0
0-24 mo
3001-5000 33 1/3% .5 0 .5 50% 0
25-36 mo
Bulldozer Center Bracket
0-3000 100% 6 0 0 0 0
0-24 mo
3001-5000 33 1/3% 1.5 0 1.5 50% 3
25-36 mo
Straightening Blade
0-3000 100% 3 0 0 0 0
0-24 mo
3001-5000 33 1/3% 0 0 0 50% 3
25-36 mo
C-Frame Hinge Pins
0-3000 100% 8 0 0 0 0
0-24 mo
3001-5000 33 1/3% 2 0 2 50% 4
25-36 mo

All parts removed (with the exception of cores used for Caterpillar
Remanufactured parts) should be rendered useless and scrapped immediately
upon completion of the repair.
Attach. (1-Rework Procedure)
(2-General Information)
(3-Optional Rework Procedures)
Rework Procedure
ADD SINGLETREE EXTENSION
1. Remove the blade group, singletree, and c-frame from the tractor as
described in the Service Manual.
2. Fabricate one Plate A using the dimensions in Illustration 1.
3. Fabricate two of Plate B using the dimensions in Illustration 2.
4. Weld the fabricated plates together as shown in Illustration 3.
5. Bore the hole in all three plates to 63.46 +/- 0.05 mm.
6. Press a 7J9351 Bearing into the top and bottom bores only.
BORE THE C-FRAME TOWER TO ACCEPT 2" SINGLETREE PIN
1. Bore all four ears to 51.25 +/- 0.08 mm.
INSTALL BEARINGS, THRUST WASHER AND NEW PIN IN C-FRAME
1. Machine the collar in the c-frame to accept the thrust washer and
bearings as shown in Illustration 4.
2. Fabricate one Spacer D using the dimensions in Illustration 10 or use 1-
6Y4389 Spacer.
3. Install the 2-6D0217 Bearings, one Spacer D or 1-6Y4389 Spacer, and 1-
6Y4388 Bearing-Thrust as shown in Illustration 5.
3. Install a new 6Y4392 Pin in the c-frame using a new 3G8887 Collar.
NOTE: If replacing early version pivot pin with two-bolt retainer,
order 1-4B4043 Bolt, 1-4D3704 Washer, 1-5B2079 Spacer, and 1-
6Y0458 Retainer. On later version pivot pin, reuse the existing
hardware.
4. When installing the bulldozer on the pivot pin, check the 3G8932 Cross
Pin connections for excessive looseness due to wear. Replace if
necessary.
INSTALL 2.0 INCH ID SPHERICAL BEARING IN THE TILT CYLINDER
1. Remove the 9J7964 Bearing from the singletree (pin end of tilt
cylinder).
2. Install a 9M1328 Bearing in the tilt cylinder.
ADD WEAR STRIPS TO THE SINGLETREE SLIDER
NOTE: It is important that all contacting surfaces are smooth and flat
before using wear strips.
Sliders should be rebuilt so that the surfaces directly under the
6Y5763 and 6Y5765 Wear Plates are smooth and provide even
support. To account for the added thickness of the wear plates,
machine 6.4 mm off the front (forward) face of the sliders.
1. Drill two holes in the end of each slider as shown in Illustration 6.
2. Install 2-6Y5763 and 2-6Y5765 Plates-Wear in the ends of the slider.
Since each wear strip is about 6.4 mm thick, at least one 4T1363 Shim
(10 mm) and possibly one 4T1364 Shim (2 mm) will need to be added under
each wear plate. Ten longer 7X0453 Bolts will need to be used to attach
the wear plates.
NOTE: A deflector can be added over the LH slider area to reduce the
possibility of dirt accumulation in the slider area.
When the wear strips are new, the contact area between the wear
strip and slider may be small. As time goes on, and the wear
strips start to wear, the contact area will increase and the wear
rate will decrease.
INSTALL THE C-FRAME SINGLETREE AND BLADE
1. Fabricate two of Spacer A using the dimensions in Illustration 7 or use
2-6Y5002 Spacers. These spacers will be placed above and below the tilt
cylinder ear.
2. Fabricate one Spacer B using the dimensions in Illustration 8 or use a
6Y5862 Spacer. This spacer will be placed above the top plate of the
singletree extension.
3. Fabricate one Spacer C using the dimensions in Illustration 9 or use a
6Y5863 Spacer. This spacer will be placed between the lower plates of
the singletree.
4. Install the c-frame on the tractor.
5. Install the singletree on the tower using a new 6Y0689 Pin Assembly,
tilt cylinder, and spacers.
NOTE: If replacing early singletree pins with separate retainer, reuse
the 2-7B3235 Bolts and add 2-1B8074 Washers and 2-5P1076 Washers.
****** IMAGE: SEBE4100.01001.001
CAPTION: Illustration 1 - Dimensions For Plate A
****** IMAGE: SEBE4100.01001.002
CAPTION: Illustration 2 - Dimensions For Plate B
****** IMAGE: SEBE4100.01001.003
CAPTION: Illustration 3 - Location of Plates A and B
****** IMAGE: SEBE4100.01001.004
CAPTION: Illustration 4 - Collar Modification Dimensions
****** IMAGE: SEBE4100.01001.005
CAPTION: Illustration 5 - Bearing, Spacer, and Thurst Bearing Location
****** IMAGE: SEBE4100.01001.006
CAPTION: Illustration 6 - Dimensions For Holes In Slider
****** IMAGE: SEBE4100.01001.007
CAPTION: Illustration 7 - Dimensions For Spacer A (or use 6Y5002)
****** IMAGE: SEBE4100.01001.008
CAPTION: Illustration 8 - Dimensions For Spacer B (or use 6Y5862)
****** IMAGE: SEBE4100.01001.009
CAPTION: Illustration 9 - Dimensions For Spacer C (or use 6Y5863)
****** IMAGE: SEBE4100.01001.010
CAPTION: Illustration 10 - Dimensions For Spacer D (or use 6Y4389)
GENERAL INFORMATION FOR REWORKING POWER ANGLE TILT
BULLDOZER BLADES ON D4H AND D5H TRACTORS
When rebuilding the pin joints, there is an important machining relationship
between the vertical and horizontal pin bores. This relationship must be
achieved in order to obtain the correct load sharing between the singletree
pin, the C-frame pin and the slider wear surfaces.
Ideally, the singletree pin assembly centerline should be in direct alignment
with the cross-pin bores of the pivot pin. (See Illustration 1). With this
alignment (and the dozer blade attached) the slider wear plates should make
flat contact with the dozer blade surfaces shown in Illustration 2. This
arrangement assures the highest loads are carried by the large pivot pin.
The bore for the thrust washer, in the C-frame, should be maintained as shown
in Illustration 3. If the bore for the pivot pin thrust bearing is cut too
deep into the C-frame, the bottom of the dozer blade is carried further
toward the back. This results in angular contact between the blade
components and the singletree slider wear plates. Rapid wear then occurs
because only a small portion of the upper and lower ends of the wear plates
contact the mating surfaces. A bending moment will be imposed on the
singletree pin if there is insufficient clearance between the slider wear
plates and blade surfaces to accommodate this misalignment. This allows the
blade to tip without binding on the singletree wear plates.
Blade movement (or looseness) will also occur if the dozer blade center
bracket bores wear. Newer dozers have a 6Y4734 Bearing for the upper ear and
a 6Y4385 Sleeve (that is harder than the former 4T0112 Sleeve) for the lower
ear. Earlier dozer blades without the upper bearings can be modified.
The dozer blade may be bowed or bent backwards at the ends causing the
relationship between the dozer center bracket and the welded tapping strips
to be altered. Angular contact between the blade and singletree sliders will
occur. If the center bracket bore location is not within the specification
given in Illustration 4, the blade should be straightened using a 50 ton
press.
Shims are provided between the bolt-on wear plates and the tapping blocks
that are welded on the blade. Clearance between the slider wear plates and
the blade surfaces should be kept at 1.0 to 3.0 mm. Shims that are removed
should be inserted under the bolt head but on the outside of the bolt-on wear
plates. This will make sure that the bolts do not bottom out. Tilt the
blade all the way in both directions to make sure there are no high spots to
cause binding.
It appears that the early grooved singletree pins cause the tower bores to
wallow out more than the later pins with a retainer that is welded on. The
grooved pins tended to rotate in the tower rather than the singletree rotate
around the pin. To make repairs, the bores are welded and machined. It may
be simpler on the D4H, as well as with the D5H Tractors, to bore the tower
ears to accept a 2.0" diameter pin instead of the original 1.75" diameter
pin.
Parts Needed For The D5H Tractor
Quan. Part No. Description
2 2X0346 Bolt
2 8G5258 Spacer
2 7X0583 Washer
If the spacers are not readily available, they can be fabricated from steel
tubing as shown in the illustrations.
It is imperative that the pin bore in the singletree is parallel to the
slider surfaces. Sliders should be rebuilt to the original 35.0 mm thickness
and the surface directly under the 6Y5763 and 6Y5765 Wear Plates made smooth
to provide good support. To account for the added thickness of the wear
plates, machine 6.4 mm off the front (forward) face of the sliders. This
will allow flush contact between the dozer blade and slider wear plates.
Some dealers may find it easier to machine the 6.4 mm from the tapping strip
wear surface, leaving full thickness for good bolt thread engagement.
Initially, this appears to be acceptable but may lead to problems at some
future time if a new 6Y5878 (D4H) or 6Y5815 (D5H) Singletree is installed.
These singletrees are used with the 2.0" diameter pins and are machined to
accept the wear plate lugs. The problem occurs in that these sliders are
repositioned on the singletree to account for the front wear plate thickness.
With machined tapping strips, the blade will be pulled rearward 6.4 mm from
vertical.
****** IMAGE: SEBE4100.01001.011
CAPTION: Illustration 1
Singletree Pin Assembly
And Pivot pin Intersection
****** IMAGE: SEBE4100.01001.012
CAPTION: Illustration 2
Slider Wear Plate Contact
****** IMAGE: SEBE4100.01001.013
CAPTION: Illustration 3
Critical Dimensions
(D5H Tractor Shown)
****** IMAGE: SEBE4100.01001.014
CAPTION: Illustration 4
Center Bracket Bore-To-Welded Tapping Strip Dimensions
Optional Rework Procedures
When rebuilding the singletree and pivot pin areas dealers may find some
other points of looseness that should also be repaired.
A. Modifying retainer of singletree pin assembly
B. Blade Straightening
C. C-Frame Hinge Pin Bore (New) Clearance*
0.37-0.63 mm (.015"-.025")
D. Bulldozer Blade Center Bracket Assembly And Trunnion (New)
Clearance*  0.35-0.61 mm (.014-.024")
* When wear causes the bore clearances to increase to 1.27 mm
(.050") or more, the looseness may be objectional to the
operator.
MODIFYING RETAINER OF SINGLETREE PIN ASSEMBLY D5H TRACTORS WITH 6Y0666
(1.75") OR 6Y0689 (2.00") PIN ASSEMBLIES
1. Use the dimensions in the following Illustration to fabricate a new
retainer plate from 16.0 mm thick T-1 steel.
****** IMAGE: SEBE4100.01001.015
CAPTION: Fabricate Retainer
From 16.0 mm Thick T-1 Steel
2. Obtain two 7X0346 Bolts, two 8G5258 Spacers and two 7X0583 Washers.
3. Cut the original retainer off the pin assembly. Weld the new retainer
plate to the pin with a 16.0 mm fillet weld around the inside of the
35.0 mm diameter hole.
4. Drill and tap the retainer bolt holes in the tower for
5/8" - 11 bolts.
BLADE STRAIGHTENING
Even after alignment of the singletree pin and pivot pin bores, there still
may be a location problem between the dozer blade center bracket and the wear
plates (tapping strips). See the following Illustration. If the bracket
location is not within specifications. it will be necessary to straighten the
blade in a 50 ton press.
****** IMAGE: SEBE4100.01001.016
CAPTION: Surface Must Include Wear Strip Surfaces On Both Ends
Of The Dozer Blade. The 10 +/- 3 mm Dimension Must
Be Measured From This "Combined" Surface
C-FRAME HINGE PIN BORES
D5H Bracket  88.92-89.08 mm (3.500-3.507")
Pin Assembly 88.45-88.55 mm (3.482-3.486")
Sleeve Bearing I.D 88.84-89.00 mm (3.498-3.504")
Sleeve Bearing O.D 114.27-114.37 mm (4.499-4.503")
Main Frame Bore 114.118-114.194 mm (4.493-4.496")
The brackets are heat treated steel castings and have a hardness of Rockwell
C 14-25. Welding up the bores for refinishing with E7018 Welding rod will
leave a softer material of approximately Rockwell C 10. Harder rod such as
E11018 is preferred as it leaves a deposit of approximately Rockwell C 25
hardness.
Rather than welding up the bores an alternate procedure can be taken.
The 3.5 inch diameter hinge pin bores can be reconstructed by the adding
sleeve bearings as follows:
1. Order four 8K6276 (Sleeve) Bearings
2. Bore the 4T1326 Bracket ears to 104.82 +/- 0.038 mm (4.1269 +/- .0015").
Bore four ears in line.
3. Install the 8K6276 Bearings flush with the inner surfaces of the bracket
ears.
4. Weld a large washer (with an ID larger than the 3.5" dia pin) over the
bearing which is pressed into the bracket ear without the retainer bolt
holes. See the following illustration. Several lugs could be welded
around the bearing to prevent it from moving out.
****** IMAGE: SEBE4100.01001.017
CAPTION:
BULLDOZER CENTER BRACKET PIN JOINT WEAR
Size New
Bracket Upper Ear Bore 44.50 - 44.66 mm (1.752 - 1.758")
Bracket Lower Sleeve ID 44.50 - 44.66 mm (1.752 - 1.758")
4T0172 Trunnion Ends 44.05 - 44.15 mm (1.734 - 1.738")
4T0172 Trunnion Bore 44.50 - 44.66 mm (1.752 - 1.758")
3G8932 Pin 44.05 - 44.15 mm (1.734 - 1.738")
Later bulldozers have a hardened 6Y4734 Bearing in the bracket's upper ear
while the lower sleeve has a 6Y4385 Sleeve. Earlier blades without the upper
bearing can be modified as shown in the following Illustrations.
****** IMAGE: SEBE4100.01001.018
CAPTION: Location of Parts
****** IMAGE: SEBE4100.01001.019
CAPTION: Bearing Dimensions