Few questions about 1998

[clunk]

I just bought a 1998 last week with 120k on the clock and of course AW4/242 combo. It runs great, gobs more power than my old 1990 and far quieter/less rattly...plus it has cupholders! I had it checked by the local Jeep dealer and it checked out okay, the test drive went well so I bought it. I'm used to my old Renix Jeep, so I have a few questions about this one.

Now that I've put some miles on it, I'm noticing that when I stop at a stop light, then start from a stop it sort of "clunks" into drive. It doesn't feel like the transmission is slipping, it's more of an entire drivetrain clunk. I did some searching and read about the slip-yoke splines drying out and causing the same clunking and since the transmission shifts smooth as silk I'm assuming it's the slip yoke, but is there any way I can check it for my peace of mind? Another possibility is the the PO had a weeping transmission line replaced a few weeks ago. I've also read that using the wrong fluid can cause the same problems, so if the slip-yoke checks out okay I'm going to have the fluid/filter replaced as well in case the shop that did the work refilled it with the wrong fluid.

Also, the A/C blows hot and the vents blow hot, even on the cool setting. To me, this sounds like a blend door getting stuck. Does this sound likely?

 

[Tim_MN]

Remove the rear drive shaft and lubricate the the slip yoke with anti-seize. While you have the shaft out, replace the u-joint. Some drive line lash should be expected due to age and mileage.

Make sure the A/C has a full charge of R134a coolant. Open the hood and see if the hot/cold cycle coincides with the cycling of the A/C compressor.

 

[joe_peters]

When you take off from a stop try holding the TC shift lever down and see if that makes a difference, it could indicate the torque bar bushing is dry/bad. Also, don't forget to check your trans and motor mounts, and definitely check the components as Tim described. Someone posted a thread here about chasing a clunk and it turned out to be the front shock grommets at the shock towers.

 

[winterbeater]

Just run the AC and see if one of the lines going into the firewall gets very cold or starts to frost up. If not, you're probably low on "freon". If it has insufficient charge, the compressor only kicks in for a second or two. If you find the cold line, bad blend door is a possibility.