Home tool making ideas, for a DIY 5R55N Overhaul, though easily written than done.

This transmission has a lot of issues, needing special tools and skills when being overhauled.

Some special tools:

Flex plate alignment tool, needed ?, for replacing a cracked flex plate (vibrations) or replacing the TC.

Oil pump alignment tool, included in a Transgo Shift kit, needed for aligning the oil pump after replacing the flow valve and for problems concerning OD, OD planetary.

A sleeve kit for OD and Intermediate worn servo bore holes (pressure loss), special tools needed.

A Valve body sleeve kit needed in cases of extreme bore/valve wear (pressure loss), special tools needed.

There are some good video clips and repair manuals concerning different 5R55N problems in the net.

Take all this to mind before you start your endeavour.

Tips and tricks

Removing a retaining snap ring in clutch drums (piston) that are under spring force.


Needed tools:

-Drill stand for an accurate vertical bore hole.
-Wood saw either hand, jig, circular
-circle, ruler, rectangle
-8mm, 10mm drill bits

Needed material

1x M10 Threaded rod
3x M10 nuts
3x large washers
5x M8 fully threaded long bolts (length?)
10x M8 nuts
10x M8 washers

If extra bolt illustration is used

5x M8 nuts (as lock-nuts)
5x M8 large washers to bend


a) 1x M10 threaded rod, 3x nut and a 2x +large washer.
b) 10x M8 nut, 10x washer.
c) Pressure plate made out of waste material, such as a thick peace of press-wood or plywood. Mark (circular) needed diameters, if using an offset grove add one offset length measured from bolt centre to middle point grove. Divide circle into 72° (5) parts. Drill 5 eight millimetre holes and a centre hole of 10mm.
d) M8 nut, washer.
e) 5x M8 long bolt with a sawed, filed grove or see top middle illustration.

1) 5x M8 Bolt fully threaded.
2) 5x M8 lock-nut
3) 5x large washer
4) Sawed of bolt head flag.

Procedure: slide washer on bolt, lock washer (lock-nut), bend washer over flange, unlock washer, saw flag off, fit washer to needs.

f) Press ring made out of a strip of spring band steel, wound up to the needed diameter and nearly to the gap width (e or 3-4) of the pressing screw. To secure against unwinding wrap a few rounds of tape around the circumference, then further secure with a length of wire wound around 2 to 3 times and ends twisted or a hose clamp in that diameter.

g) Use a good length of hose to protect the clutch drums fine finished surface (oil pressure lose!) from being damaged (scratched) through the rode thread!
h) In some cases an extension block my be needed.
i) Ground plate.
j) M10 nut, large washer.
k) Press ring rolled up.
l) Press ring band.

Measuring clutch tolerance without a dial guage:

Illustration top right

a) caliper position
b) caliper position
c) Caliper
d) snap ring
e) clutch package
f) halved clutch drum
g) clutch piston

Before disassembling, with the snap ring still fitted, measure the distance from top drum to snap ring top (a, green), remove snap ring, measure the thickness of the snap ring (a,d), add both measurements together to get length (b,red) (note). Replace clutch package, measure distance from top drum to top back-support plate to get length (b, blue), subtract red value from blue value to get the tolerance. Use tolerance values given from the Superior Shift Kit instruction manual (0.030 - 0.05 inches? 0.8 - 1.3 mm)

Out of tolerance, gap to wide: picture bottom right

Make out of two clutches one (1), shave off clutch material from one side of each clutch plate (green), take care and pay attention to which side you shave off. The direction of rotation has to be the same as if it were one clutch plate (red).

Automatic Transmission 5R55N

Tips and tricks

Thoroughly clean the transmission's outer casing before entering it.

Work in a good illuminated, dirt, dust (sand) free environment (clearances of under 0.02 mm) preferably a bench covered with a tough plastic foil with its edges bent upward (oil spilling mess).

Use a transmission service kit that supplies a pump alignment tool (Transgo, ...). Read its installation manual carefully.

Flex plate alignment tool (See note) will be needed if flex plate has been removed from TC, when for instance broken (Vibrations). Read its installation manual carefully.

An alignment tool (Rotunda Part #307-403) must be used to align the adapter plate to the TC. When using the tool it is important to note: Use one round hole and one oblong hole before tightening the nuts holding the adapter to the converter.

Mark the position of parts and bolts with different lengths, that are not obvious to fit (make pictures).

Brake band adjustment, turn the adjustment screw to its end position (hand feeling), then tighten with 72 in.lb, then loosen 1 turn. Check output drive shaft that it turns freely.

Some technical modifications must by worked off: (Short over view)

Over drive planetary needs more splash oil feed (lubrication, heat transfer).
a) Oil pump output orifice needs a larger bore hole.
b) 4 holes crosswise have to be drilled through the (OD) sun gear adapter plate.
c) Valve body spring and valve changes
d) OD and Intermediate bore wear (repair sleeve), skill, special tools needed.

Running in the transmission will take hours and probably a hundred kilometres or more before clutches, brake bands and counter part surfaces have adapted to one-another, this will result in extreme shifting conditions and erratic behaviour until given parameters are met, take care.

General Service Information

General Service Information

Rear axle

Rear sub-frame

Front axle

Lower ball-point joint, Shock absorber bushes, Stabilizer bar links + mounts

Brake disc and pads


Intake Manifold / Ignition Coils / Spark-plugs/ engine-block ventilation (elbow)


Starter system

Valve clearance, timing-chain, tensioner and glides:
With valve clearance in its tolerance, there was no need to take the camshafts down, so tensioners and co. have to wait, the good thing is the tensioner pumps up in 3-4 min. the rattle noise disappears.

Cruise control malfunction, emergency mode

Automatic Transmission 5R55N

Info, tips, Fail Safe Mode

Stall Speed Test procedure and diagnoses

Valve Body, known issues

Valve Body, Solenoid test procedures

Line Pressure Test

Self made press for pressing down clutch drum springs, checking clutch tolerance without a dial gauge


Air Conditioning

Miscellaneous repairs

Wind-shield-wiper mechanism:
Time on the lot took its toll, wind-shield-wiper shafts had seized, uninstalled the mechanism, freed the seized shafts through the use of a good rust loosener, heat, force.

Water in Spark-plug wells 3-2 cylinder:
After days of heavy rain the engine began to misfire with accounted trouble codes, spark-plug wells were wet, an ionized rusty red path on the ceramic insulator had developed which shorted the HV ignition spark.

Connected the radio controls to the multi-functional steering wheel using an analog digital converter.