What gears do I need?

JeepBeast

New Member
Original poster
Joined
Jan 30, 2021
Messages
4
Location
Alabama
Hey guys I'm new to the forum and I hate to ask a question that I'm sure has been answered but I have a 98 tj se with the 2.5l and the 3 speed automatic transmission. I'm currently running 33x12.50 tires and want to change my gears but I have no idea what I need to go with. Yes my jeep is my daily driver and yes I would like to be able to get up to speed on the interstate. I know a V8 conversion is the best thing to do but that's just not in the cards right now. Any help would be greatly appreciated
 
4.56 is the correct gearing for your 3 speed (30RH) and 2.5L for 33/12.5
 
Are you doing the gear swap?
If you're paying it will cost you fairly close to doing a v8 swap if you get creative.

A 2.5 is ok in a manual in stock form. I mean just "ok" and "only" on stock form.

One mod to the Duke knock off and it's massive power zapping. Like going from low power to absolutely no power.

If you insist get the lowest gear possible...a 5.13

It will help a little but please know it will be a little.

A v8 is ultimately the way to go. Save up a few bucks and drop in 4 more cylinders.
 
Are you doing the gear swap?
If you're paying it will cost you fairly close to doing a v8 swap if you get creative.

A 2.5 is ok in a manual in stock form. I mean just "ok" and "only" on stock form.

One mod to the Duke knock off and it's massive power zapping. Like going from low power to absolutely no power.

If you insist get the lowest gear possible...a 5.13

It will help a little but please know it will be a little.

A v8 is ultimately the way to go. Save up a few bucks and drop in 4 more cylinders.
I understand and I appreciate the recommendations. I agree with you completely. However this 2.5 and myself have become very acquainted with one another in the past 20 years that I've owned her and I know all her ins and outs very well. I just want to keep running optimally as long as I can until I'm able find the v8 conversion I want and can afford. Also yes I'll be doing the gears myself with the aid of some more experienced friends.
 
  • Like
Reactions: Jerry Bransford
JeepBeast, I understand the " acquainted with one another " feeling.
4.56 , 4.88 gears will do wonders in helping overcome the diameter and weight of the much larger Wheels/tires.
Go with gears as long as you understand the limits of the D-35.

Personally I don't see how you could do a comprehensive V-8 conversion for similar money to gears.
Once you start down the rabbit hole of new axles, cooling, proper mounting, shifters, driveshafts, and electronics the
costs and time / tools to properly do the conversion gets real pricey fast.
Besides, after you would do the V-8 conversion you probably wouldn't like the current gear ratio and want to change it🤪
 
  • Like
Reactions: Jerry Bransford
The thing about an engine swap is that you would still want to regear to run that engine in its power band. The two projects are not mutually exclusive.
 
  • Like
Reactions: D M
JeepBeast, I understand the " acquainted with one another " feeling.
4.56 , 4.88 gears will do wonders in helping overcome the diameter and weight of the much larger Wheels/tires.
Go with gears as long as you understand the limits of the D-35.

Personally I don't see how you could do a comprehensive V-8 conversion for similar money to gears.
Once you start down the rabbit hole of new axles, cooling, proper mounting, shifters, driveshafts, and electronics the
costs and time / tools to properly do the conversion gets real pricey fast.
Besides, after you would do the V-8 conversion you probably wouldn't like the current gear ratio and want to change it🤪
Trust me when I tell you a v8 swap can be real close to a R and P swap. We do them both here.
Paying a shop to install gears (which is exactly what i asked) you better believe it's going to get real close in cost in particular if he or she can get creative sourcing a v8 and its parts.

Just doing a R&P you are looking at 6 bills for the parts at a minimum. Then looking at 12 hours labor time which is going to be around a grand give or take.
Since it's all apart why retain an open differential so now there's that possible/probable expense.
Even doing a lock right style that's another 4 bills and only goes up if doing a Detroit or selectable. Doing front and back locker? X2 to the locker cost. Are we upgrading axles too since it's all apart? There's that expense now as well.

A v8 swap if being creative...
The engine could be anywhere from free to xyz...but being realistic let's use $500 for the engine.
The tranny could again be free to xyz but let's use $500 for it.

Motor mounts
$100-200

$500 adapter

Everyone these days has this love affair with Amazon (they shouldn't)
but ...... I just seen a radiator not long ago for a v8 in a wrangler for around $100.
Pending the exact tranny and where this all gets placed (should do a mock up first) can determine driveshaft need.. both, one, none...
Pending some things a V8 swap can get damn close to a shop doing a r&p swap. Particularly if the OP has some luck and scores some components on the cheap.
 
Trust me when I tell you a v8 swap can be real close to a R and P swap. We do them both here.
Paying a shop to install gears (which is exactly what i asked) you better believe it's going to get real close in cost in particular if he or she can get creative sourcing a v8 and its parts.

Just doing a R&P you are looking at 6 bills for the parts at a minimum. Then looking at 12 hours labor time which is going to be around a grand give or take.
Since it's all apart why retain an open differential so now there's that possible/probable expense.
Even doing a lock right style that's another 4 bills and only goes up if doing a Detroit or selectable. Doing front and back locker? X2 to the locker cost. Are we upgrading axles too since it's all apart? There's that expense now as well.

A v8 swap if being creative...
The engine could be anywhere from free to xyz...but being realistic let's use $500 for the engine.
The tranny could again be free to xyz but let's use $500 for it.

Motor mounts
$100-200

$500 adapter

Everyone these days has this love affair with Amazon (they shouldn't)
but ...... I just seen a radiator not long ago for a v8 in a wrangler for around $100.
Pending the exact tranny and where this all gets placed (should do a mock up first) can determine driveshaft need.. both, one, none...
Pending some things a V8 swap can get damn close to a shop doing a r&p swap. Particularly if the OP has some luck and scores some components on the cheap.
If your doing all those upgrades for a regear wouldn’t you be doing them for a v8 swap as well? I wouldn’t run a Dana 35 on 33’s behind a v8 unless I had done a super 35 kit and lockers and a regear as well......
 
  • Like
Reactions: ColoJeep