Audi A5 Gearbox Issues: Transfer Case Oil Problems

Having some experience with transmission repairs, I dealt with a very similar issue on my 2013 Audi A4. Started with the same symptoms, rough shifting and slipping between gears under acceleration. After noticing gear grinding sounds getting worse, I took it to a workshop. The diagnosis revealed defective gears in the transfer case caused by mechanical wear. The transfer case oil was contaminated with metal particles, indicating significant internal damage. The repair involved: Complete transfer case inspection, Replacement of worn gear components, Fresh transfer case oil, Full transmission diagnostic check Total cost came to 330 Euro including parts and labor. The repair solved the issue completely, and the transmission has been shifting smoothly since. Before suggesting specific solutions for your A5, could you share: Current mileage, When did the symptoms first appear, Any unusual sounds during gear changes, Whether the issue occurs more in cold or warm conditions, Service history regarding gear oil changes This information would help determine if your issue matches what I experienced with my A4.

Thanks for the detailed reply regarding gear oil wear patterns. In my case, I first noticed the symptoms about 2000km ago at 61000km. Currently at 63855km with the last service done at 55000km. The grinding noise is most noticeable during cold starts and gets slightly better after warming up. Already checked the transmission fluid level which appears normal, but I am concerned about potential gear wear inside the transfer case causing these symptoms. Based on your experience, the repair cost seems reasonable if it resolves the issue completely. Will get it checked soon to prevent further damage from oil leakage or worn components.

Thanks for providing those details. After solving my A4's transfer case issues, I learned that cold-start grinding is often a telltale sign of transfer case oil problems, similar to what you're describing. Since your symptoms match my previous experience, especially the cold start behavior improving after warmup, it strongly suggests transfer case wear. The timing also aligns, as mechanical wear typically becomes noticeable around 60000-70000km when oil starts losing its protective properties. Looking back at my repair, catching it early was key to preventing major gear damage. The oil leakage in my transfer case started small but quickly led to accelerated wear. Getting it fixed at 63000km likely saved me from a much costlier repair. One tip based on my experience: request the workshop to check for metal particles in the old transfer case oil during inspection. This analysis helped confirm the wear source in my case and guided the specific repairs needed. Given the similar symptoms and mileage to my situation, I expect your repair costs should be in the same range unless additional issues are found. The 330 Euro I spent was worth it considering the smooth operation since the fix.

Thanks for sharing such a helpful case about transfer case problems. Those symptoms match what I am experiencing quite closely, particularly the cold start behavior. My mileage being around 63000km when these issues appeared does seem to follow a similar pattern. The grinding noise in cold conditions and improving after warmup definitely points toward the gear wear problems you mentioned. Given that mechanical wear tends to accelerate once it starts, I will schedule a workshop visit this week to prevent more extensive damage. I will specifically request they inspect the transfer case oil for metal particles and check for any oil leakage around the seals. The 330 Euro repair cost provides a good reference point, though I understand costs may vary depending on what they find during inspection. Better to address potential gear wear issues now rather than risk more expensive transmission repairs later. Will update once the workshop completes their diagnostic check and repair work.