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97 TJ w2.5L Throw me some ideas

Hey sam I saw a TJ D30 with 4.56 gears for sale on OfferUp. Might be a step in the right direction. Was around $150 I think with no knuckles

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I've had 2 TJ's with the 4 bngr and 33's. I regeared both to 4.88's. It still struggled but would do 70-75 on the highway in 5th gear. Around town and off road it made a BIG difference. Sweet spot on that motor doesn't even really hit until 3K RPM's and they'll run at 4K all day and not sweat.

Also remember...it's a square block on wheels.
My 95 on 4.10 gears and 5 speed with 35's still cruised at 70.
It was slow getting there but it did it.
And I only used 5th down hill.
Yours sounds like the motor is lacking power. More than the usual 2.5 lack of power.
Do a compression test, check for a partially plugged cat, or a flat cam lobe.
Rather than make a decision based on opinions, why not actually troubleshoot it instead of throwing money at it. First off, do a compression test both dry and wet. Post up pix of the spark plugs. Do a vacuum test, both at ideal and at 3500 rpms in neutral.

Grab a timing light and measure the timing at idle and 3000 rpms.

Get a loaner pressure gauge at Autozone and measure the fuel pressure both at idle and at speed under load.

Take a pix of the tail pipe for soot etc.

Post up your results and I/we can help tell you what is going on with the engine. All the gauges you need are available on the loaner program at Autozone. If you need help in performing the tests, post up and I/we will instruct you step by step.
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My dad had a 95 YJ with the 2.5. He put on custom d44s with 5.68 gears and a very heavy flywheel. It had to towed to trails after that, but it could climb anything.
I run a YJ with a 2.5 and anyone here who has seen me at the crawl can tell you the 2.5 will take a beating and love every minute of it. I work mine over pretty good. I put a d44 from an XJ in the back and regeared it and the front disconect d30 to 4.88's and put lockrites in them and never looked back.
i have a header and tb spacer on the engine, electric fan and I found a stage two cam for it moons ago. on the exhaust i left the cat and put on a dynaflow muffler .
Dont remove the cat takes away from the low end torque the 2.5 likes ai little back pressure to run right .
keep in mind when you talk 5th gear and highway speeds two things , the better off road the worse on road .and the rwangler body style is as aerodynamic as a brick and in reality was never designed to go over 60 by its original design see 1942
No real solutions to offer but I drove a 95 YJ with a 2.5 and 5 speed for work for about 2 years. Stock tire size and gears I could jam up to about 80mph here in the bay area. Only thing that I can tell that was done to it was a thermostat delete. the 2.5 is gutless but should still get up to decent speed