Overheating Issue

A few months back I killed my alternator with mud and mud clogged the fins of my radiator to where I would overheat every 10 mins. Got it home replaced the alternator and for the radiator I just power washed the front and the rear (didnt take it out). It was perfectly fine after that, I got 34s and temps were still good until I decided to drive to Colorado Springs or Boulder where there are long inclines. Now, I know they will kill my power but my heat would shoot to the line right before the red, as soon as I level off it goes back down to 210. I went wheeling and driving the steep mountain roads it almost overheated, it cooled down once I got to the top and started to air down I was fine on the trail until I hit anything going uphill that required some gas. I just thought it was weird because when I was flat or short hills I was fine, but the long ones were just shooting the temp up.

I am wondering if I did not get all the mud out of the fins. Or something else in the cooling system is not working. But the thing I am hoping is that it is just the stock 3.55s in the axles that is making the engine and tranny work harder (I have a B&M cooler).

How old is your rad?

More than likely stock 1996. Would you see a need to overhaul the entire cooling system?? Water pump, tstat, radiator, lines??

A 10 yr. old rad is probably in need of replacement, especially if it has not received good maintenance under previous owners.

If it was my XJ, and I decided to change the rad, the hoses (all of them) would automatically be changed right along with the rad. I might even do the t'stat.

The water pump would depend more on miles. If it's the OEM water pump, and has more than 100K on it, I would for SURE replace it.

Well I bought this dealer 2 years ago so I do not know specifics on the parts. The XJ has 150k on it, stock rad, stock tstat, stock waterpump. I think when I get paid ill get all new crap but a CSF 3 row.