Are Transmission Problems Causing Your Converter to Fail? By Ed Lee and Maura Stafford

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1 Are Transmission Problems Causing Your Converter to Fail? By Ed Lee and Maura Stafford There are many transmission-related problems that can directly affect the functioning and longevity of the torque converter. If these problems are misdiagnosed, the converter can be blamed. Even worse, if the transmission problem is not corrected, repeat converter failure can occur. Some transmission-related problems that can be manifested as converter problems include: Restricted coolers Worn or wrong pumps Worn or stuck valves Worn bushings Incorrect fluid Bad solenoids or sensors Pressure problems 2004 Sonnax fax:

articles Maura Stafford The Desk Jockey Project Engineer with Sonnax for more than 10 years Currently works out of a home office in Georgia Primary design work is

2 Ed Lee The Wheelman Sonnax Technical Adviser Owner/operator of Deltrans Inc. transmission shop since 1982 Charter member of the TASC Force Seven years ago started TASC Force Tips column in Transmission Digest and continues to contribute articles Maura Stafford The Desk Jockey Project Engineer with Sonnax for more than 10 years Currently works out of a home office in Georgia Primary design work is developing Transmission Specialties products Actively involved with the TASC Force since its inception Technical articles have been published in Transmission Digest and Gears magazines fax: info@sonnax.com

1-800-274-7890 Converter shops are entitled to a free subscription to Transmission Digest.

3 Converter shops are entitled to a free subscription to Transmission Digest. This monthly publication has many technical and managerial articles, industry news, new product announcements and company profiles fax: info@sonnax.com 3

Sonnaflow Diagnostic Tool Sonnaflow is a machine that measures and records cooler flow Important diagnostic tool Instrumental in the development of many of the TASC Force solutions The Sonnaflow

4 Sonnaflow Diagnostic Tool Sonnaflow is a machine that measures and records cooler flow Important diagnostic tool Instrumental in the development of many of the TASC Force solutions The Sonnaflow offers these unique features: Can measure flow during a vehicle road test Provides an easy-to-read electronic display in gallons per minute Easy to install and remove from any vehicle Reduces warranty comebacks. Can pay for itself by identifying just one cooler problem Helps detection of blocked coolers Helps prevention of burned planetary or bushing failures Easier and more accurate than traditional (1-quart-in-20-seconds) measurement method Superior to bulb-style glass tube-flow meters: no bulky hoses, quicker to install, more accurate over a wider range of temperatures and viscosity changes Can be used with a dynamometer to measure flow and pump output Can easily be connected to a lab scope Detects subtle variations in flow that cannot be detected with other test methods Also a great teaching aid! fax: info@sonnax.com

5 Basic Test Sequence Note: Any testing while the vehicle is moving should be performed with two people for safety reasons. One person must remain focused on safe operation of the vehicle. The second person can monitor and record the Sonnaflow measurements. Observe the Flow Rate during the following 3 Basic Operating Conditions: Idle This is the same test as the traditional 1-quart-in-20-seconds measurement. Observe the flow with the vehicle at idle in drive range with the brake applied. The flow at idle should be the lowest flow rate of the 3 conditions with a minimum flow of 0.7 to 0.8 GPM. Some vehicles may have lower idle rates. Cold ATF may also contribute to lower idle flow rates. Recheck the flow when the ATF is warm. In-Town Driving Observe the flow while driving the vehicle at low to moderate speeds with your foot on the gas (not coasting). This is a TCC off or no-lockup condition. The flow during in-town driving conditions should be considerably more than at idle (approximately double). Highway Driving (Lockup) Observe the flow while driving the vehicle in highway cruising or other lockup conditions. During lockup conditions the flow should show a noticeable variation from the in-town flow. The flow will normally increase during lockup but may decrease on some vehicles. In either case the change should be noticeable. Note: Some vehicles are not equipped with a TCC and never achieve lockup conditions therefore, this 3rd operating condition cannot be measured. Diagnosis A Problem: No flow or low flow (less than 0.5 GPM) at idle OR No increase in flow during in-town driving. Cause: Either problem is usually due to a flow restriction either internal to the transmission or external to the transmission (e.g. blocked cooler). To help determine the cause and location of a flow restriction, follow the procedure below: Determine if the restriction is internal or external to the transmission. Bypass the cooler and re-run the flow test. If the flow does not increase, then the restriction is internal to the transmission. If the flow does increase, then the restriction is external in the cooler or cooler lines. If the cooler is blocked, it should be disassembled and repaired or replaced as needed. Note: In extreme cold weather a cooler blockage may be the result of gelled ATF. Re-test when warm. If the flow restriction is internal to the transmission, the following possible causes should be checked: Low oil level Clogged sump filter Mismatched pump parts A pressure regulator valve that is stuck in its bore High boost pressure Lockup valves that are stuck Plugged drainback fitting Diagnosis B Problem: No flow change at lockup Cause: Lockup is not occurring. Two potential problems should be investigated: The electrical signal is not being sent to the solenoid(s) responsible for inducing lockup One of the valves related to lockup is leaking or stuck in place NOTE: Some vehicles do not go into lockup Some pulse width modulated (PWM) transmissions exhibit only a small change in flow during lockup. This is common in Ford AODE and AXODE transmissions. The flow must be observed closely to detect the lockup condition. Use of the optional output signal adapter with a graphing lab scope can assist in detecting the flow change during lockup in PWM transmissions fax: info@sonnax.com 5

E4OD/4R100 Transmissions Complaint: Converter clutch crowding on reverse engagement Cause: Generally low pump volume at low RPM Excessive tolerance = low pump volume Standards: 1.

001 E4OD Pump Correct method for measuring outer gear to cavity clearance. The OEM pressure regulator valve shuts down the cooler circuit in idle, or if there is low pump volume.

6 E4OD/4R100 Transmissions Complaint: Converter clutch crowding on reverse engagement Cause: Generally low pump volume at low RPM Excessive tolerance = low pump volume Standards: 1. Converter hub to inner gear:.004 max radial 2. Face to pocket:.001 min,.002 max 3. Tip to tip:.0025 per side,.005 total radial 4. Outer gear to pocket" total radial Pump housing flatness:.001 E4OD Pump Correct method for measuring outer gear to cavity clearance. The OEM pressure regulator valve shuts down the cooler circuit in idle, or if there is low pump volume. Results can be converter overheat and Code 62 problems. A common industry trick for fixing these problems is to drill a hole into the casting wall of the pump. This allows line pressure to feed lube and converter feed full time. The downfall to this fix is that it also allows converter drainback, which can create delayed engagements. E4OD Pump Casting wall drilled fax: info@sonnax.com

The Sonnax pressure regulator valve has an encapsulated check valve that allows full-time flow to the cooler circuit, yet prevents converter drainback.

7 The Sonnax pressure regulator valve has an encapsulated check valve that allows full-time flow to the cooler circuit, yet prevents converter drainback. An orifice has also been added to use regulated line pressure to assist the balance circuit in overcoming EPC pressure. E4OD Converter Conditions Complaint: TCC comes on and stays on after 1-2 shift Correction: Inspect vehicle wiring harness: brake or stop light may have been rewired TCC solenoid defective Complaint: TCC cycling on-off-on, often misdiagnosed as slip in 4th gear Correction: Defective RPM sensor, FIPL or TPS Inspect battery voltage and voltage drops across ground Complaint: Engine stall forward or reverse Correction: Defective MLPS or wiring Pump has excessive warpage and cross leakage Plugged turbine shaft or mixed stator and pump cover Defective converter piston seals or piston run-out/clearance Complaint: Code 62, repetitive, or under heavy use Correction: Cracked TCC piston Excessive converter cover run-out or piston run-out Insufficient converter apply psi, poor converter regulator spring Upgrade to the F5 or later casting # high capacity pump Ensure filter is flowing well Install high capacity cooler lines and radiator Be careful with pump, lube and pressure regulator modifications Suggest clearance of between turbine and cover after weld fax: info@sonnax.com 7

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AX4N/AX4S/AXOD/AXODE Transmissions Complaint: Converter seal leak Cause: Insufficient drainback Seal composition Torque converter integrity Correction: Drill additional drainback holes.

11 AX4N/AX4S/AXOD/AXODE Transmissions Complaint: Converter seal leak Cause: Insufficient drainback Seal composition Torque converter integrity Correction: Drill additional drainback holes. Suggested 2 holes (one at 3 o clock and one at 9 o clock) Do not use silicone seals. Use Viton seals only. Install Sonnax FD-90-29G flanged hub into torque converter. Complaint: Possible lockup shudder Code P0741, P1728, P1744, or P0743 Cause: Incorrect lockup solenoid Correction: Install correct solenoid fax: info@sonnax.com 11

12 Complaint: AXOD No TCC apply AX Series Converter Conditions Correction: Seal up the valve body end plugs, repair the drainback check valve pockets, replace the bypass control sleeve with Sonnax part K Test TCC solenoid for sealing with 12 volts Defective oil pump shaft, loose inner tube or plugged with stator cap material Complaint: AXODE/AX4N Code 628/1744, No TCC Correction: High resistance ground. Repair grounds or add additional from ECU Comparable situation with improper sprocket ratios Turbine sensor coil to reluctor clearance excessive Complaint: AXODE Poor converter fill, low pressure Correction: Poor cover alignment, would gall the oil pump shaft sealing rings Restricted oil pump shaft Complaint: AXODE TCC applies at 2nd gear shift or does not engage; coastdown chuggle Correction: Installing the wrong TCC solenoid or separator plate combination without matching ECU/controller. The gray case connector identifies unit with PWM/TCC solenoid and its matching separator plate. The white connector identifies unit with on-off TCC solenoid and plate. Complaint: AX4N Code 628; No TCC feel of apply; TCC chuggle on deceleration Correction: Oil pump shaft restricted or loose internal tube Defective MCCC solenoid Worn valve body at bypass control valve or sleeve Turbine sensor (channel plate near axle) clearance excessive Poor ground circuits for the ECU create erratic/no TCC and high psi fax:

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18 4R44E/55E & 5R44E/55E Transmissions Complaint: Converter seal leak Cause: Poor seal composition Bad pilot sleeve Misalignment Correction: Replace silicone seal with Viton seal Replace pilot sleeve Check center line (transmission to motor), if fax:

AODE/4R70W Transmission Complaint: Delayed or no lockup Shudder condition Converter code 628 Uncontrollable TCC Cause: When too much oil is routed to the plunger valve, the bypass valve has slow

19 AODE/4R70W Transmission Complaint: Delayed or no lockup Shudder condition Converter code 628 Uncontrollable TCC Cause: When too much oil is routed to the plunger valve, the bypass valve has slow reaction from the MCC/TCC solenoid oil, delaying lockup. Excessive wear at the control sleeve allows regulated converter charge oil to exhaust, resulting in no TCC apply conditions. Correction: Install Sonnax replacement control sleeve and plunger kit K. The sleeve has a smaller feed orifice, allowing the bypass clutch control valve to properly stroke to the TCC apply position. The matched sleeve and valve restore correct clearances for hydraulic integrity fax: info@sonnax.com 19

20 Complaint: Delayed forward engagement Engine surge or stall at idle Converter shudder Cause: Low baseline pressure Correction: In 1996, Ford made a change to both the pressure regulator valve and the valve body casting. The valve spool locations were changed slightly, and the spool diameter controlling line to converter feed was stepped. This spool step, in conjunction with regulating notches added to the valve body casting, allows converter feed to be regulated. Due to these OEM modifications, installation of a stronger spring to raise baseline pressure (ideally 68 psi) without a specially modified regulator valve will result in restriction of converter charge and converter release circuits. This may cause the engine to stall or surge at an idle or create converter shudder. The Sonnax kit K contains a properly metered PR valve and stronger spring for 96-up valve bodies. Sonnax spring can be used by itself in the valve bodies. AODE/4R70W Converter Conditions Complaint: 4R70W Code 628 after rebuild Correction: Wrong planetary gear ratio, an AODE set was used instead Complaint: AODE TCC Shudder; No TCC apply; Code 628 Correction: Change fluid to Chrysler 7176 or Mercon 5 Install a new converter bypass control sleeve, Sonnax part K Inspect the bore at the TCC bypass valve largest spool diameter Install the updated TCC modulated solenoid Verify friction is not glazed and TCC piston taper does not exceed.0017 Inspect stator support for wear at the TCC sealing rings or bushing Complaint: AODE TCC stalls motor after transmission work Correction: Pinched wire from transmission service or valve body work Aftermarket TCC control defective, shorted and applying TCC Complaint: AODE Front seal leak; ballooned converter; engine crank thrust failure Correction: Excessive converter regulator pressure Re-spring converter regulator valve fax: info@sonnax.com

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Chrysler RWD Transmission Complaint: Delayed engagement Lube failure No converter charge in park Converter drainback Converter bushing failure Pressure regulator buzz Cause: Poor converter feed

23 Chrysler RWD Transmission Complaint: Delayed engagement Lube failure No converter charge in park Converter drainback Converter bushing failure Pressure regulator buzz Cause: Poor converter feed pressure due to OEM pressure regulator valve design OEM manual valve does not allow converter charge in park Correction: Install Sonnax Lube Regulated Pressure Regulator Valve, part number 22771A-02K Install Sonnax Manual Valve, part number fax:

24 Complaint: Lockup shudder Overheated converter Reduced cooler flow Soft TCC apply Build up of release pressure during lockup Cause: The OEM 4-spooled switch valve stroke is insufficient to control circuit timing of applied vs. release pressures. Correction: Install Sonnax modified 4-spooled switch valve, 22771A-01, which improves timing & flow to the apply and release circuits fax:

25 TASC Force Tech Tips Article, February 2004 Transmission Digest fax:

Chrysler RWD Converter Conditions Complaint: 42RE No TCC after rebuild; slow converter fill or repeated lube failure Correction: Mismatched pump halves with large and small suction ports Mismatched

26 Chrysler RWD Converter Conditions Complaint: 42RE No TCC after rebuild; slow converter fill or repeated lube failure Correction: Mismatched pump halves with large and small suction ports Mismatched large suction port case with small port valve body Switch valve stuck open towards spring Complaint: 42RE Delayed engagement together with ballooned converter Correction: Worn pressure regulator reducing valve, aggressively drilled line-to-lube Complaint: 47RE Rapid or repeated converter friction failure; soft TCC; no TCC apply or clutch not releasing Correction: Bond lining where OE was floating Alter converter stall on diesel units Adjust line to 80 psi (idle drive) install Sonnax switch valve Verify cooler flow minimum is.7 gpm idle in drive, 1.6 gpm TCC off cruise and gpm TCC applied Install a quality Teflon seal on the turbine shaft Verify the turbine-to-cover bushing/bearing is centering the turbine Resurface the pump stator, and recess the bolt holes in pump body Set up pump pocket to gear side clearance at max of.0015 OE had some turbine shafts with feed hole too small, inspect for update fax: info@sonnax.com

27 Complaint: 47RE Sensitive TCC in-out Correction: Defective TPS, suggest automatic replacement after 50K Open the exhaust slot in the separator plate Complaint: 47RE TCC stalls engine in reverse Correction: Verify cooler flow is not restricted Problem generally related to release oil flow. Open the exhaust circuit outer circuit of switch valve Reseal the turbine shaft rings at the stator, air check of input shaft Ensure oil flow of release circuit in the converter is not restricted fax:

AODE ( 96 & LATER) SC-AODE-1. Transmission Reconditioning Kit FULL COMPATIBILITY IMPORTANT VALVE BODY PARTS REASSEMBLY PARTS

AODE ( 96 & LATER) SC-AODE-1. Transmission Reconditioning Kit FULL COMPATIBILITY IMPORTANT VALVE BODY PARTS REASSEMBLY PARTS AODE ( 96 & LATER) Transmission Reconditioning Kit FULL COMPATIBILITY SC-AODE-1 Full compatibility with 1996 and later units. Identified by alignment pins with 10mm head and.173" pin diameter. IMPORTANT