VW Suran Trans Warning: Fluid vs Major Repair Tips

Having some experience with transmission issues, I faced a similar problem with my 2015 VW Golf. The automatic transmission symptoms were nearly identical, erratic shifting and warning lights, which also put the car in limp mode. After taking it to a workshop, they diagnosed an undervoltage issue affecting the transmission control module. The hydraulic fluid levels were actually fine, but the electrical system was causing the transmission to behave erratically. The repair involved testing and replacing some electrical components related to the transmission control unit, costing 240€. The slipping transmission symptoms completely disappeared after fixing the electrical issue. This type of problem can sometimes be misdiagnosed as a fluid issue, which is why proper diagnostics are important before doing an oil replacement. To better assist with your specific case, could you share: Has the battery been tested recently? Are there any other electrical issues like dim lights or slow starter? Does the problem occur more frequently when using power-hungry accessories? Have you noticed any correlation between the transmission issues and weather conditions? This information would help determine if your issue matches what I experienced or if its something different requiring another approach.

Last service was done 2800km ago and included a full check of all systems. Following up on your electrical theory, I noticed the battery warning light flickering occasionally, especially when using the AC. The slipping transmission symptoms do seem worse during cold starts and when multiple electrical systems are running. The starter has also been a bit sluggish lately. The transmission problems started becoming noticeable about two weeks after these electrical symptoms appeared. The automatic transmission issues are most evident during gear changes between second and third, with occasional jerking movements. Given my hydraulic fluid levels are normal according to the dipstick check, your theory about electrical problems affecting transmission performance makes sense. Will have the battery and charging system tested before proceeding with any transmission repairs.

Your latest description really reinforces my suspicion about the electrical system being the root cause. The battery warning light, sluggish starter, and problems during cold starts match exactly what I experienced before the transmission started acting up. The automatic transmission behavior youre describing, especially the jerky shifts between second and third gear, is a classic symptom of low voltage affecting the transmission control module. When the electrical system cant maintain proper voltage, the transmission performance suffers and eventually triggers the emergency mode. In my case, the alternator was actually the culprit, not delivering consistent voltage to the transmission control unit. The entire repair, including a new alternator and testing of the transmission control module, cost around 580€. Much better than a full transmission rebuild. Recommend getting the charging system tested first. A failing alternator or weak battery can cause the slipping transmission symptoms youre experiencing. The transmission oil and hydraulics are likely fine since your fluid levels check out normal. The fact that your issues worsen with AC use strongly suggests an electrical origin, just as it did in my situation. Once the charging system was fixed, the transmission returned to normal shifting without any additional transmission work needed.

Thanks for sharing the electrical system diagnosis. The symptoms you described match my situation perfectly, especially how the automatic transmission problems get worse when using power-hungry accessories like the AC. Since my car has similar issues with the battery warning light and sluggish starter, I'll definitely have the charging system tested before pursuing any transmission repairs. The slipping transmission behavior during cold starts also aligns with your experience. Just booked an appointment to have the alternator and battery checked first. Really hoping its an electrical issue like yours rather than needing major transmission work. The 580€ repair cost you mentioned for the alternator replacement is much more manageable than a full transmission rebuild. Will update once I get the results from the electrical system diagnostics. Makes complete sense to verify the charging system before assuming hydraulic fluid or internal transmission problems are to blame. Thanks for helping narrow down the likely cause, this could save me from unnecessary transmission repairs.