My credit union is offering a expended warranty for $58/month for 36 months with no mileage limit. $500 deductible. The truck has over 120K miles.
Considering if it will cover the whole exhaust.
I would make sure it covers the exhaust before purchasing, but still not too bad considering it's a diesel, IMO. Injectors alone will cost you more than the cost of the warranty! Rock Auto shows them at ~$380 each after the core charge, so with 8 holes to plug you're at $3K. Driving a diesel ain't cheap!
My used car warranty on my 2012 Ram did not cover the exhaust or any emissions related parts. It was weird, but i still got my monies worth from it with a whole new front end (ball joints tie-rods etc.) and a few other miscellaneous fixes.
Just my $0.02