maybe cat is clogged. have you done a compression test ?? a tuner would help it feel like a beast

 

Haven't done a compression test yet and sadly a tuner is out of my budget right now

 

the power your looking for is like a dangling carrot here....its always one more suggestion away...lol... with that gearing and larger tires the truck isnt going to be a speed queen...as far your compression? if you have weak cylinders there goes more power.... deathflash?...theres more gone....when you have exhausted all the rest of the usual weaknesses and your still not quite satisfied the fact that its a magnum motor and only had 245hp max from factory pushing a 5000 lbs truck around is the final straw that breaks the camels back...

 

Your blinking 4x4 light is going to probably be one of two things. The sensor is either going bad, or you have a vacuum leak. My money is on the vacuum leak, as it is a very common problem on these trucks. The 4wd is vacuum actuated at the front axle, and when you lose some, but not all of the vacuum, it causes it to not be able to fully engage or disengage (depending on the location of the vac leak). I had this happen to me several years back. There are three other clues that might help you determine if it is a vacuum leak or not. One is that it will cause the 4x4 light to blink at a speed equal to your RPMs and driving speed. The faster you go and higher rpm, the faster it should blink until it is either solid on or solid off. As you slow down and came to lower rpms, the blinking should slow down till it was again solid on or off. The second hint is if you also happen to have the famous problem of your air vents changing of to the defrost position under acceleration. When you have a vacuum leak, and you go full throttle, all blowing vents will shift to the defrost position. This is the safety position, i.e. if you ever lose all vacuum, you will at least be able to keep your windshield clear. The third clue is if your cruise control is currently working correctly or not. If not, it is probably a vacuum issue. Good luck.

 

Welcome to the DF!!! With 225K miles on it, you should consider seafoaming it.

 

I had the same problem on mine. There is a vacuum connector on top of the transfer case just below the shifter boot. It is easier to get to from the bottom. There are two lines that start as flex then are coupled to hard lines that follow the cross member then bolt to the frame near the accuator on the front axel, they then go back to flex line and to the accuator. Where I found my leak is some dill hole redid the exhaust and angled the cat just so it would wear through the hard line and cause my 4WD light to stay on and even better the accuator not to engage not lockin the front axel makining you think you are in 4WD but on having 3 engaged to the drive train. My light too would blink on and off depending on RPMs as stated above. Have fun!

 

Funny how a thred goes south and needs to be put back on track. Did not Think it was coming back until Silver_Dodge chimed in.

 

Thanks for all the replies guys, will def. check out those vacuum lines once the rest of the ice melts off my driveway (we had a mini-blizzard up here in KS over christmas). Speaking of snow, I think I may need to retract my statement about the 4x4 *always* engaging when I put it in 4HI. Just didn't feel like it was grabbing the way it should in the snow.....