Ok so I used to belong to the facebook page but it was shut down in lieu of this forum, and now I am here with an issue that has me puzzled. I have a 95 with the 4.0 (HO). Its struggling producing top end power and even is somewhat weak on the low end. I've replaced spark plugs and a bad alternator for the electrical system (problem existed before this) which did seem to pep it up some. Also I have replaced the fuel filter. The rubber connecting lines had dry rotted and were leaking and after inspecting fuel filter decided it needed changing as well. Well I've noticed two things, not only is my throttle cable seemingly stretched (temporary fix for that did determine it wasnt the power loss issue) but despite gaining some low end pep it refuses to carry the power to higher rpms. Is this catalytic converter? Throttle position sensor? Maybe timing? I'd doubt timing since it idles fairly smoothly for the 4.0s I have encountered. Just very slow revving and does not at all drive like the other 4.0s I have had particularily in cherokees which were often heavier. Some info the prior owner made some changes to the drivetrain mostly beefed it up, I have not researched who or what but it's still Dana family for the differentials. I have 32x11.5s, and the AX15 transmission.