Is this something to be overly conserned about? i have a 99 with a "53" block, it has 175,000 miles on it with no cracks. Does anyone know for instance how many "53" were produced, and how many cracked? Is there any kind of preventative measures that can be taken?  

i dont know how many were produced or how many cracked but i bought a 99 with 125,000 miles and it was cracked when i got it  

http://www.stamey.info/Truck/Cummins53BlockFAQ.htm

this will tell you everything you need to know  

Cummins says that if they go 120000 miles without cracking they wont crack so its in the clear.  

sandslinger79:
Cummins says that if they go 120000 miles without cracking they wont crack so its in the clear.

not true all the time though, i had a friend who had a 175k on his, completely stock when it cracked on the passenger side just like the rest.  Id still be leary about going for maxium power on that block or even sled pulling too much until you truly feel comfortable that itll hold  

they seem to crack at random. i know guys with 53 blocks who have modified them and done pulls and drags and had no problems. but then out of the blue it will crack just driving it around.  

All I know is when anyone spends $35,000+ on an Diesel truck, you sure as hell shouldn't be getting cracks in your engine block - EVER!  (Unless of course you are an idiot and let the coolant get too watered down and it freezes - nobody can protect against stupid - LOL!)  For that matter, anyone who even buys a used diesel should not be expecting to have a cracked block ever, unless due to maintenance negligence!  I grew up on a farm, and we've had dang near every size and make diesel out there.  NEVER have we had any engine block cracks or major engine failures - NEVER.  John Deere, Perkins, Minneapolis Moline, Allis-Chalmers, Ford, Yanmar, Mitsubishi, older Cummins, Cat, Detroit, and more...  Many of these engines have put on a lot of hard hours (as most off-road equpiment does), been lugged, and just plain worked.  So, from my experiences, I gotta say, these 1998-200? Cummins ISB 5.9L's are trash.  (Boy, I never thought I'd say that - being a Dodge Ram Diesel fan...)  Any engine block that cracks for "no apparent reason" is trash in my book.  Look, I have owned (2) 1999 24 valve trucks, and the first had no issues, but only had 125,000 miles on it.  I sold it, and never had a problem.  Perhaps it didn't have a "53" block?  (I'm sure it did, but perhaps it didn't - I know I never checked.)  In fact, I miss my 'ol '99 shortbox.  But, I was probably just lucky that that one didn't crack yet.  The 1999 24V 5.9L longbox truck I have now is a complete pile of *** and I wish I'd never have bought it.  It has 205,000 miles on it and the crack is a good FOOT+ long!  It leaks the cooling system dry in 100 miles of easy highway cruising with a light trailer load!  The worst thing is that I was naieve and didn't even know that it was a problem on the truck until I was on my way home with it from the private party (a-hole, liar) that I bought it from.  Now, I'm stuck with it and am going to have to spend a fortune on getting the motor out, welded up, and put back in.  Quite frankly, depending on cost, I may just opt to just part the whole damn truck out and cut my losses, before the tranny goes in it.  (After all, we all know that the Dodge truck automatics always blow up eventually to the tune of $2,500+!)  With my luck, I'll fix the motor and blow the tranny the following day!  I'll no doubt be watching the new 6.7L's closely, and will not be buying any more "53" block 5.9L's EVER again!  I haven't sworn off Dodge yet, but dare I say it... the Ford's are looking better all the time.  At least the Navistar blocks don't CRACK for no reason!  Thanks for reading my rant...  AJ