On my truck ( 01 ram 2500 5.9l V8 46 RE trans) the transmission broke down two years ago and it was rebuilt. The shop bypassed the cooler in the radiator and installed a 11x7 in transmission cooler at the front that I replaced for a 17x11 mastercooler. I did the band adjustments, replaced the fluid - they used mercon there, left the lock nut loose...[:@] - My question is: is it safe to keep as it is now or should I replace the radiator and reroute the pipeline ?

 

Lemme see if I got this straight ... you're running an 11x17 external trans cooler that you want to take off and replace with a stock trans cooler in a radiator?

Why?

 

Sounds to me that you replaced the external cooler with a different one, and are wondering if it will be OK to run with the external one and not use the one in the radiator. My answer would be yes unless you live in Canada or a bordering state where it gets real cold where you might need the radiator to warm the fluid.

 

Thank you for your reply. I live in NJ. I just never saw nobody doing this.

 

I think the external cooler is actually superior
but pay extra close attention to the hoses and fittings that shop used.
Use only the highest grade crimped on fittings on at least 1,000 psi rated hose.
Absolutely do not use hose clamps on slip in fittings.

Since the shop used mercon instead of ATF+3 or 9602
and left the lock nut off
you ought to ask this Canadian place

http://dieseltrans.com/dodge/index.htm

who is the 'authorized shop' in your area for installing Dieseltrans parts.
Then go to that shop (which should be technically skilled)
and have them do a 'check up' on your transmission operation and line pressures.