Properly maintained, an engine should be expected to last more than 75,000kms without catastrophic failure.
If you've got clear evidence of proper servicing (particularly dealer servicing) id be having a word to the dealer and/or jeep again. It wont be fully covered but you should at least get some assistance- try whispering 'ACCC' and 'acceptable quality' if they need encouragement.
https://www.accc.gov.au/consumers/co...mer-guarantees
From accc site
Since 1 January 2011, the following consumer guarantees on products and services apply.
Products must be of acceptable quality, that is:
safe, lasting, with no faults
look acceptable
do all the things someone would normally expect them to do.
Acceptable quality takes into account what would normally be expected for the type of product and cost.