Good day!

Your picture looks like you have a 2004 or newer, which would make all my thoughts on this a little iffy!! My first E53 was a 2001... Silver... Picked it up pretty cheap from a dealer in Illinois... Had a slipping and thumping upon medium to hard acceleration... No issues at all doing the normal gentle take-off... I had to replace the transfer case chain that was stretched... The issue I have here is that you have a 2WD until you need more traction... So, unless the rear tires are slipping by more than 5% difference from the front, you won't be in AWD and you probably won't suffer from a stretched chain in the TC...

Everything I read in your symptoms say stretched TC chain... But unless the TC is locked in AWD all the time, I'm just having doubts that is the problem...

Any others out there have insight?!

Good luck!!!

Cheers!!

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2001 E53 X5 4.4i (03-07-2001 build date) White exterior / hellbeige interior (6MT swap vehicle - Manny)
2002 E53 X5 4.6is (12-20-2001 build date) Imola Red exterior / M-texture interior (Red)
2003 E53 X5 4.4i (06-26-2003 build date) Silver exterior / Black interior (Silvester II)
2008 Mini Cooper S ragtop (04-17-2008 build date) Dark Silver exterior / Gray interior ( Topless)
BMWCCA member (#4745)