I've done a bunch of searches, but I wanted to get some feedback on likely diagnosis.
Baiscs: 90XJ 4.0 with the closed system. 3.5" lift, 31" AT's. Recently replaced t-stat with OEM, replaced pressure bottle and cap (Renault OEM cap).
Problem: Temp has been creeping up for several weeks on long drives. Mostly on hills the temp seems to creep up way more than it used to, and it seems more variable than it used to be. I drove up I5 from LA to San Fran tonight and in a couple of spots (over the Angeles mtns and the pass from 580 into the Dublin valley - both long grades) the temp crept up to near red. On the ride over the mountain, I had to stop before it went all the way red. Sat for 10-15 minutes, temp cooled down and went on my way. Outside temp was in the 90's. Once I got over the mountain and into the valley, temp went to 100 or so, so I kicked on the A/C. Temp creeped quickly up towards red, so I shut off the A/C. The temp came down, but very slowly, and stuck at around 215 or so, and stayed there for most of the ride. Eventually the outside temp dropped and I was able to use the A/C, but kept a close watch on the temp.
Oh yeah, at one point when I stopped and opened the hood, I noticed that the upper hose was sort of bulging at the top of the t-stat housing. I didn't see any leaks, and the systems seems to be holding pressure. I'm not taking any chance with the hose, so it will be replaced.
Solutions I think I need:
1) Good system flush
2) Fan Clutch & hoses
3) Radiator
4) Water pump
My question is, given that the ability of the system to keep the truck cool is degrading, which of the above is the likely culprit? Is it even possible to tell, or do I just start with the cheap stuff first and work my way up? I'm not sure I'll be able to do the 7 hour flush bit - apartment, no access to hose - so I'm thinking jiffy lube or stealer for a straight fluid flush.
Am I on the right track here?
Baiscs: 90XJ 4.0 with the closed system. 3.5" lift, 31" AT's. Recently replaced t-stat with OEM, replaced pressure bottle and cap (Renault OEM cap).
Problem: Temp has been creeping up for several weeks on long drives. Mostly on hills the temp seems to creep up way more than it used to, and it seems more variable than it used to be. I drove up I5 from LA to San Fran tonight and in a couple of spots (over the Angeles mtns and the pass from 580 into the Dublin valley - both long grades) the temp crept up to near red. On the ride over the mountain, I had to stop before it went all the way red. Sat for 10-15 minutes, temp cooled down and went on my way. Outside temp was in the 90's. Once I got over the mountain and into the valley, temp went to 100 or so, so I kicked on the A/C. Temp creeped quickly up towards red, so I shut off the A/C. The temp came down, but very slowly, and stuck at around 215 or so, and stayed there for most of the ride. Eventually the outside temp dropped and I was able to use the A/C, but kept a close watch on the temp.
Oh yeah, at one point when I stopped and opened the hood, I noticed that the upper hose was sort of bulging at the top of the t-stat housing. I didn't see any leaks, and the systems seems to be holding pressure. I'm not taking any chance with the hose, so it will be replaced.
Solutions I think I need:
1) Good system flush
2) Fan Clutch & hoses
3) Radiator
4) Water pump
My question is, given that the ability of the system to keep the truck cool is degrading, which of the above is the likely culprit? Is it even possible to tell, or do I just start with the cheap stuff first and work my way up? I'm not sure I'll be able to do the 7 hour flush bit - apartment, no access to hose - so I'm thinking jiffy lube or stealer for a straight fluid flush.
Am I on the right track here?