7455 US Highway 87 East, San Antonio, TX 78263, US
Kosub Transmission Service Inc

Gerald Kosub Transmission Service Inc.
Transmission Rebuild in San Antonio


Computer Diagnosis & Testing


  • Our shop provides the latest and greatest scan testing technology in order to determine what is actually going on with your transmission. Automatic transmissions have evolved dramatically in the last 20 years. They have improved the way they operate with revolutionary electronics, on board computers and software. What this means to you is, your vehicle is best serviced by a company like ours that stays up to date with cutting edge technology and repair information. Electrical diagnosis is a necessity when properly fixing a transmission problem.  We have all the specialty equipment in our shop needed to perform your transmission repair or re-build. We stock all parts we need for our most popular cars and trucks. 


Transmission San Antonio

Gerald Kosub Transmission Service Inc in San Antonio

Transmission Rebuild & Overhaul

  •  The key to a successful transmission repair, re-build or replacement is properly diagnosing the problem. With the transmission still in the vehicle our tests are done. Scan testing first to check for codes, then checking recent data that had occurred when the problem first happened. Transmission oil pressure gauge tests and a test drive if possible to confirm the customer’s complaint. This can then lead to dropping the transmission pan to get a visual inspection of debris in the pan and sometimes testing electrical components individually, solenoids, switches, pressure control solenoids and internal wiring harnesses. After a proper diagnosis is done then we will know what procedure is needed for our customer’s transmission.Then the transmission is removed from the vehicle and taken to the bench. Once completely dismantled, we can see the extent of the damage and what lead up to its failure. The parts are cleaned and inspected and a working list is made of materials needed to re- build the transmission. The reassembly procedure then begins pressing in new bushings and seals reassembling clutch packs and replacing bearings. These sub-assemblies are placed into a high pressure cleaned transmission case and torqued to specifications. Valve bodies get cleaned and re-built with new solenoids or replaced with new assemblies. The units are air pressure checked for proper operation and leaks. With the rebuild complete, the transmission cooler and lines are flushed with a hot flush machine to guarantee a sterile system. The transmission is installed with a high quality rebuilt  converter. All vehicles are filled with a fully synthetic fluid, then scanned and road tested monitoring the transmission performance on the scan tool data stream. The vehicle goes back to the drive on lift for a visual inspection and quality control. 

Transmission Service & Maintenance


  • We provide maintenance for your automatic transmission. First we remove the pan and clean in our high pressure parts washer, remove and replace the internal and external filter when applicable as well as replace the fluid with a vehicle specific full synthetic fluid. We also offer an additional transmission flush through the cooler and lines when needed. This service should be done at 60,000 mile intervals. Call today to get a price. We offer the highest quality customer service and will treat your automobile as if it is our own. 

Performance Products

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