is re-gearing on stock tires worth it?

[optmaxx]

I've recently installed a home made bored out throttle body that matched the gasket opening, and wow, it really opened up my stroker and it's a lot more fun to drive. So that got me wondering about re-gearing with stock tires and a three speed transmission (TF999)?

My tire size is stock 235/75R15, my gearing is 3.07 with the TF999 3 speed auto, and I have steel rims and a hard top so it's probably heavier. It definitely feels like a higher end 6 cylinder, and it's more fun to drive than my friend's 5.0 explorer, but I'd like to be able to chirp the tires and have a bit more power going up hill. I'm able to chirp the tires on a dirty or wet road, as well as on turns haha.

Like I said, it's way more fun to drive, but I think the gearing might be holding it back, and you can feel it when going uphill once it hits 2nd gear. It doesn't struggle going uphill but it feels like it can do better based on my experience driving other cars.

I was thinking of going to maybe 3.73s? I mostly do street driving, but I do take it on the freeway when I have to since it's my daily, and it can hit 80mph pretty easy, but I don't stay at 80, I mostly cruise at 70mph cause it feels safer. So does anyone here re-geared to a lower gear with stock tires? Was it worth it?

[75SV!]

I can't say with stock tires. Well, maybe I can. I have an '88 MJ. I ran stock tires on it. I do not know what gears were in it. I decided to lift it etc. Still, in the works though. I gave the rear end to a neighbor, as his MJ rear end busted. He said it drove some much better. Did someone put in a 3.55 to replace a 3.07..??
Now I have regeared from 3.55 to a 4.10 with 31's. Stock motor. My main problems was inclines in WV. Bore TB, header, 2.5 cat back. All helped. Changing to 4.10s really changed things.
I do have an XJ on 31's with 3.73s. It feels more like stock. Not bad, although with a miss and some other issues, it did get bogged down at some inclines. I haven't run it much yet with the mini-stroker. Still, has a miss.
So, my thoughts are, it depends on your 'terrain' and weather a slight decrease in MPG. I'd say 1/2 a mile per gallon. You might see an increase though, if more hills and say city or country driving.

[Gorilla]

This thread is a bit aged at this point but I just finished changing the gears on my '04 Rubicon 5spd nv3550 in January from 4.10 to 4.56 with 33s on a 2.5" lift. Stock was 31s. I've had this since new on 33s so I'm really familiar with it. I live in CO and always had issues holding speed at the tunnel on I-70 at 11,000 feet elevation. Along with a set of HS 1.7 fixed roller rockers that is no longer an issue on my otherwise stock 4.0. I changed the gears myself.

It comes with some downsides though. One of the stock driveshafts has always had a tiny imbalance that showed up around 78mph. It's now spinning 10% faster and showing up at 70mph. The rpms at a given speed/gear are 10% higher too and it feels a bit more high strung, particulary on our 75mph+ highways. I knew what I was trading off and ran the numbers through grimjeepers gearing calculator to help me think through whether it would do what I wanted at particular ratios. Determined 4.88s would be annoying on our higher speed highways in the west. 4.56 came with some trade offs.

If you haven't already made the change I'd make sure you know your current ratio and run some numbers in a gear calculator to understand the new rpms at various speeds. You've got 3.07s and some 3.73s would definitely make it feel quicker. But this job is a bit of a time consuming pain even if the cost to do it yourself isn't too bad. A gear swap would probably have as much impact as your stroker build. I'd also say the current manufacturing state for gears is a bit worse than it was in the past. If you can't get Spicer/Dana gears then Revolution seems to be the next best. Most everything else moved to sources in China to hit a low price point.