Hydra-Matic Transmission (MD8) General Motors
Considering overhauling your Chevrolet transmission or just need GM 700R4 parts? We provide a large inventory selection for 700R4 automatic transmission overhaul kits, parts including steels, kits, solenoids, filters, solenoids. This wide selection of parts are used in the GM 700R4 automatic transmission in GM model years 1982 to 1993 Chevy light duty trucks and passenger cars. In addition to these kits we also supply torque converters, fluids, problem prevention kits and in most cases we can supply good take out hard parts and save you some money.
Free information is provided on parts illustrations, maintenance tips, overhaul tips and assistance in identifying just what automatic transmission you have in your vehicle. In addition a factory description and ratio information is available.
Parts Illustration Troubleshooting/Overhaul Manual |
Maintenance Tips Overhaul Tips |
Remanufactured Automatic Transmission What domestic transmission do I have? |
Description: 4 speed rear wheel drive automatic overdrive transmission. |
Ratios: 1st: 3.059 2nd: 1.625 3rd: 1.000 4th: 0.696 |
1982 - 1993 GM light duty trucks and passenger cars. Fluid Recommendation |
This is an abbreviated list and other parts are available. If you need something that is not listed just let us know. | ||||
Part Number |
Qty Req |
Description |
Years |
Price |
TM700-R4 | Troubleshooting/Overhaul Manual | 1982-86 |
$35.97 |
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TM700R4B |
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Troubleshooting/Overhaul Manual | 1987-93 |
$35.97 |
MRK5100T-S |
1 |
Master Overhaul kit w/high energy band & frictions and steels | 1982-84 |
$194.72 |
MRK5100AT-S |
1 |
Master Overhaul kit w/high energy band & frictions and steels | 1985-86 |
$201.56 |
MRK5100BT-S |
1 |
Master Overhaul kit w/high energy band & frictions and steels | 1987-93 |
$196.96 |
K51980 |
1 |
Bushing Kit | 1982-On |
$21.94 |
K51940 |
1 |
Thrust Washer kit w/Selective's | 1982-On |
$14.40 |
K51941 |
1 |
Thrust Needle Bearing Kit | 1982-On |
$38.96 |
K51949 |
1 |
Servo Apply Spring Correction Kit | 1982-On |
$23.96 |
51814 |
1 |
Forward Clutch Sprag Assembly 26 elements | 1982-86 |
$54.44 |
51841A |
1 |
Forward Clutch Sprag Assembly 28 elements | 1987-On |
$73.76 |
44815 |
1 |
Low and Reverse Roller Clutch before 6/16/86 | 1982-86 |
$25.16 |
51815 |
|
Low and Reverse Roller Clutch from 6/16/86 | 1986-On |
$25.00 |
Deep Transmission Pan | Increase fluid capacity, reduce operating temperatures, extend transmission life, convenient drain plug, increase transmission rigidity. Don't tow without the following 2 items! | Easy installation no modifications necessary. | ||
MAG700 | Add extra fluid! | Kit includes filter, gasket, bolts and pickup extension. |
$266.36 |
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External Cooler Auxiliary | ||||
LPD4589 | Long "True Cool" Lower pressure Drop Cooler 8" x 11" x 1.5" Complete kit. Remove the heat extend the transmissions life. |
$109.75 |
The following components are available to enhance Shifting | ||||
Part Number |
Qty Req |
Description |
Years |
Price |
ST51944 |
1 |
Shift Calibration kit | 1982-1993 |
$60.94 |
The following electronic components may or may not be required. | ||||
Part Number |
Qty Req |
Description |
Years |
Price |
51870U |
1 |
TCC Solenoid | 1982-1993 |
$30.95 |
51876E |
1 |
Output Shaft Speed Sensor | 1987-1995 |
$50.04 |
Torque Converter ---------- Torque Converter Problem & Information For this series transmission there are MANY different possible torque converters (not all listed here). When rebuilding your transmission it is always recommended that you change the torque converter. When ordering the torque converter you must supply the four digit code off of the existing unit (located on a sticker). Some of the possibilities are: |
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Code | Order Part Number | Application | Price | ||||||||||||||||||
C33 | NATC33C | Small Bowl 10" Code: HD, HJ, HE, SJ 1980-96: 2.8L, 3.1L and 3.4L low stall |
$20123 |
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C35 | NATC35 | Small Bowl 10" Code: HA, HB, HK, HZ, SZ 1980-1996 2.5L, 2.8L high stall |
$156.33 |
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The following modifications are also available for above converters:
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C21 | NATC21 | Large Bowl 12" Code: CG, CF, CK low stall 1980-84E, 5.oL, 5.7L Non-turbo, pads may be round or square |
$219.10 |
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C24 | NATC24 | Large Bowl 12" Code: CB, CE high stall 1980-1984E 4.3L, 5.0L turbo, pads may be round or square, use C24HP in Corvette |
$145.76 |
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C40 | NATC40 | Large Bowl 12" Code: DG,DF, DK, low stall, 1984L-1992 5.0L, 5.7L: Use C40HDT in trucks 1984L-1994 pads may be round or square |
$203.25 |
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C48 | NATC48 | Large Bowl 12" Code: DB, DE, high stall, 1984L-1994 4.3L, 5.0L, Turbo, Use C48HP in Corvette, pads may be round or square |
$156.33 |
Be sure to use our transmission cooling line flush in order to remove debris. Your cost is $11.88 order Kooler Kleen. | |||||||||||||||||
C40HDT | Large Bowl 12" Code: DG, DF, DK, low stall 1992-1994: 5.0L, 5.7L, Trucks 1987-1994: will retro to 1984L Heavy duty bearing and turbine hub |
$203.25 |
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C48HDT | Large Bowl 12" Code: DB, DE 1992-1994: 4.3L, 5.0L Turbo; use C48HDTHP in Corvette: will retro to 1984L Heavy duty bearing and turbine hub |
$202.74 |
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C37 | Large Bowl 12" Code: 1980-E84; 6.2L Diesel May us C21SQ (square pad) design as an upgrade |
$156.33 |
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C39 | Large Bowl 12" Code: 1984L-86 6.2L Diesel May us C21SQ (square pad) design as an upgrade |
$156.33 |
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The following modifications are also available for above converters:
We supply only high quality remanufactured torque converters, cost + $50.00 core deposit (some may be higher |
These manuals are typically 50 to 85 pages and contain both troubleshooting information and data to support overhaul, such as electronic data, illustrations and specific procedures and specifications. These are professional shop manuals which will give you the capability to diagnose problems, and evaluate repair options. If you decide to have your transmission overhauled at a local shop you will be armed with detailed knowledge of problems and potential fixes. This information should allow you to get the best deal, Always compare pricing for labor. If you supply the parts and ask for warranty in the end you will save money.

Red Line high-Temp ATF
Our Red Line high-Temp ATF --is a synthetic GL-4 gear oil for use
where Dexron III is recommended. A higher viscosity allows optimal operation at 70 degrees higher temperature, providing better torque converter efficiency. Perfect for heavily-loaded vehicles. Superior stability allows high-temperature operation without varnishing valves and clutches.
Recommended for use after overhaul, mixing with existing fluid is not recommended!
Our LubeGard "automatic transmission protectant" is recommended as an additive to improve transmission life and maintenance.
Typically contains gaskets and rubber kit, sealing rings, metal/rubber clad seals, friction plates, steel plates* , front and rear bushings, filter and where applicable Band* and/or Modulator*.
*not included if listed separately
Regular maintenance cycles and continued checking of fluid levels is critical to the life of your transmission. Operating temperature is the single most critical parameter effecting the life of the transmission. Keep the temperature down and fluid fresh helps the units typically last a very long time under normal driving conditions (no teenagers involved). We can supply a couple of aftermarket products to help you get the most out of your transmission:
Auxiliary Transmission Oil Cooler.
The Truco part number LPD4451 is an excellent auxiliary oil cooler to provide additional cooling capacity. The kit includes all parts required to mount the unit and connect to existing cooling lines. This is a typical do it yourself project. The unit typically mounts in front of the radiator. Your cost on this transmission life saving product is $54.94 plus shipping and handling.
Generally we don't recommend additives but we have found that the Lubegard "Automatic Transmission Protectant" at only $13.93 + S&H can:
- Prevent overheating, reducing transmission temperature up to 40 degrees F.
- Extend fluid life
- Eliminates transmission fluid foaming and oxidation
- Reduces wear throughout the transmission
- Elimates clutch chatter and torque converter shudder
- Softens and modifies harsh shifts
- Provides for smoother shifting
- Eliminates objectionable noises during shifts
- Keeps valves and governors free and frees stuck valves in valve bodies
- Raises the thermal and oxidative stability
- Only product that increases the fluids ability to transfer heat
- Contains no Ash
Always consult and follow owners manual for maintenance intervals and requirements.
Overhaul Tips
Before you tear into the transmission, we suggest you first study the troubleshooting/overhaul manual, add a bottle of our "Automatic Transmission Protectant" and put a few miles on the vehicle. This just might free valves and governors that are possible stuck in valve bodies. Be sure to get computer trouble code(s), see owners manual for technique to acquire malfunction codes. This will be a great assistance in diagnosing possible problems.
Twenty-One Steps to Successful Transmission Repair:
1) Do your research locate any technical bulletins pertaining to your transmission, ask your dealers parts department for bulletins.
2) Clean the entire transmission, including the valve body.
3) Check pump, valve body and case for warpage.
4) Flat file pumps, valve bodies, and cases. Just a few strokes with the file to knock off high spots and handling burrs.
5) Check all pump gear clearances.
6) Check planet pinion end play and side to side motion.
7) Soak all planet assemblies.
8) Soak all friction materials for 15 - 30 minutes.
9) Make sure all steels are in usable condition or replace. Do not sand or tumble steels when used against High Energy friction materials.
10) Inspect all surfaces upon which a band will ride.
11) Replace all rotating oil control rings.
12) Check all oil control rings and rubber products in the bores for proper fit.
13) Check all major support bushings and bushings that control lub oil.
14) Pre-lubricate all bushings and thrust washers.
15) Pre-lub pumps.
16) Pre-fill torque converter.
17) Use available manuals to ensure proper specifications and clearances.
18) Set correct clutch and band clearances.
19) Take the time to set the total end play.
20) Use a torque wrench on all pumps and valve bodies.
21) Always double flush the cooling and cooling return lines to the radiator to remove particles trapped there.
Take your time, take your time, take you time!
Failure modes for torque converters manifest themselves in different ways, slow Failure, i.e. loss of power over time, instant failure, i.e. input shaft spline failure. Following is a short list of problems, possible causes:
Complaint |
Possible Cause |
Reference/Fix |
Overheated Converter | TCC/PWM Solenoid filled with debris | ATSG Bulletin #98-25 |
Overheated Converter | Replace worn TCC Regulator Valve | Transgo #SK4L60E or Sonnax #77754-03k (92-97), 77754-04k (98-up) these require reamer #77754-R2 |
LOCKUP Slipping (CODE P1870) | Worn valve body casting | ATSG Bulletin #00-41 |
TCC Slipping (1994-1995) | PCM Software | ATRA Bulletin #473 |
The difference between stator design, look inside the converter at the larges set of spline's (stator shaft spline's). If the spline's are split then the unit has a dual element stator. Do not interchange single element and dual element converters.
Torque Converter Installation/Preparation
Many torque converter problems can be avoided with proper preparation:
1) Pre-thread converter bolts by hand to make sure there is no sign of stripped threads.
2) Check and clean crankshaft thoroughly. Change crank spacer (if applicable).
3) Use 320 grit sandpaper or Emory cloth to remove any metal shavings on crankshaft.
4) Check converter for any damage that may have occurred during shipping.
5) Pre-fill converter with a minimum of (1) quart of transmission fluid.
6) Clean all paint off the pilot using 320 grit emory cloth.
7) Apply grease, not transmission gel, on the pilot.
8) Check flexplate for cracks and be sure there is no more than .006" run out.
9) Make sure all engine dowel pins are in place and clean.
10) Make sure all electrical ground straps are properly connected.
11) Never, Never use an impact gun to install torque converter bolts. Driving a bolt into the converter cover will create a dimple on the lockup apply surface. Lockup clutch failure will occur when the lockup piston applies against and uneven surface. Grinding off on thread length from all lockup converter bolts is recommended to avert this type of failure.
Click to enlarge Illustration