I have a 2006 is 250, got a clunk for when going into reverse and drive. Any idea on what this might be? Axles, diff? Coming from rear of car…

 

How does it drive? Gears shift smoothly and at the right speeds? If it drives well and transmission shifts smoothly, chances are the transmission is ok.

And does the shifter engage at the middle of each position (PNRD)? If yes, chances are it’s not the transmission.

One potential cause is rear CV axle(s). Do you hear a clicking/hammering noise when driving?

 

I hear a clicking, popping noise coming from the rear. As well as clunk when putting in gear from the rear. I’m leaning towards rear cv axles and plan on doing both sides while I’m at it…

 

seems to drive and shift fine

 

Check rear CV axles. One or both might be worn out. It’s the same procedure for rear or front CV 1/2 shafts.

 

Thanks appreciate the help!

 

I don't know if you're a DIY type but seriously consider dropping the rear differential to remove the axles. Only two braces need removed vs tearing the whole rear suspension apart on both sides. It can be done with the rear tires sitting on ramps.

Its much faster than ripping the whole back end apart on both sides. The only issue people have is popping the axle out of the diff, but thats just technique. Pop one side free. Toss a spacer between the axle and diff, lower diff down and remove axle.