I have an 2007 525i BMW, just hit 100,000 miles. I bought it in 2009 (certified Pre Owned) from an BMW dealer. It had 36,000 miles. It is now all mine. All paid off. Started having issues with it jerking and slipping gears last month i was told i needed a new transmission at the cost of around $4000. (at my local mechanics shop) I've kept it in mint condition and its beautiful and did i mention it's paid off!My dilemma is repairing it at the cost and mileage of my car or selling it and getting a new car and start paying again?

I would also get a second opinion on that repair. scan the computer for codes. lots of things can cause weird shifting issues.

Thanks for the replies! Will get second opinion.

My 550 has been coined the "German money pit". With 130k on the odometer, I can't seem to part with it even though I'm now having to do several mechanical fixes (that I can manage myself in my shop, luckily). I love my car AND its character, and I genuinely like tinkering with it. If I were in your shoes, however, I'd get it rolling to a dealership under its own power and get a new one.... I do like that it is paid off, and 4k is much less than 40 (as my dad always said)

It could also be the transfer case motor, which is a lot less in cost and easier to install.