IMO, if you pull a turd out of the toilet and polish it.....its still a turd. I would imagine that with some research on here or looking at some local salvage yards, you may be able to find a D44 for the same price (maybe a bit more) as upgrading your D30. May be worth looking into.
The D44 internals are all stronger, so are the u joints. Tubes and c's are the same, as previously mentioned. Lots of information on the New Generation D44 on the Dynatrac website.
Some guys build D30's and run them with 37's and have no issues. Some guys build D60's and break them. A lot has to do with driving style and terrain. The skinny pedal breaks more gears and axles than anything else, lockers contribute.
IMO, worth what you're paying for it, is run it as is with the plan to replace it with a D44 from a Rubicon or from TF or Dynatrac. If from a Rubicon, the tubes will still need help.
I have a Rubicon D44 and I'm still waiting to bend it to replace it with a Dynatrac or TF though.
A forum community dedicated to Jeep Wrangler JK owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, reviews, engine swaps, troubleshooting, suspension, and more!