Suspension Upgrade and Down the Rabbithole

BigSkyBlue

New Member
Original poster
Joined
Apr 19, 2021
Messages
6
Location
Bozeman, MT
Hi everyone,

Longtime lurker, first time registering and posting.

I'm the proud owner of a '02 Wrangler, and have had her since 2004(!). I've put nearly 100k miles on for a grand total of 113k. Started near Chicago, and the Jeep has taken me to Indiana, Wisconsin, Colorado, Texas, and now Montana. So, several cross-country treks and a whole lot of various usage: city, desert, mudding, rock crawling, snow, etc. The Jeep has been a faithful companion to me, and, honestly, I hope to keep her for the long haul. It's been a source of transportation, fun, escape, housing, and educaton. I do my own oil changes, basic repairs, minor modifications, and whatever else that needs to be done that I can accomplish with some basic tools, a six pack, and a swear jar.
Along the way I've added a throttle body spacer, K&N CAI, 31" tires, trailer hitch, replacement windows, replacement soft top, and that's about it. Replaced a few suspension parts along the way. For the most part, I keep up with the recommended maintenance schedule. Rear gearbox leaks a little bit, but I'll swing back to that. Power steering leaks a little. Engine leaks a little, but hardly much at all. I've gotten to all of the engine codes as they've come up, but P0122 (throttle body position sensor), P0442, P0455, P0456 still plague me. A growing tick sound has increased over the years, but really only at idle when the engine is warm. When it does tick, it sounds and feels like it is coming from deep inside the engine block. I was deeply when it first started happening many years ago, but CD2 with oil changes seemed to help the situation. Not sure what you all think about those things.

Which brings me to my main line of questioning. I always told myself that when my shocks were toast, I’d upgrade and get a modest lift installed. That time is now, so I had my sights on a 2.5” suspension lift. I think I’d be happy with a little below or above that number, but I’d like to run 32” tires with ample room for articulation when off-roading. I’ve seen a number of different options on Quadratec, but having read the really good thread on lifting I understand what I’m looking for/what to watch out for. I noted that the guide recommended potentially adjusting your gear ratios… which lead me down the rabbit hole.


My Jeep has a 5 speed manual, with the stock 3.07 gear ratio. According to this chart, I’m already way off anything ideal when it comes to gear ratios. I know (and now feel particularly guilty) that I should have changed the gear tooth for the speedometer years ago (Jeep originally shipped with P225s). So, now I’m fretting about the gear ratio and lack of power. It’s not as nimble as it once was with smaller tires, and now it all makes sense. Should I not even bother at looking at bigger tires? Should I look at re-gearing before anything else?


Apologies if this was information overload, but thanks in advance for your help/input!

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Proper gearing never hurt anyone. Go the easy route and find a pair of axles from a 4cyl. Should cost less than $500, likely closer to $300.
that’ll get you 4.10’s then lift as you see fit. We all have our preferances
 
First, a big welcome to WTF which is a great forum that is very technically astute! The next is to start saving to regear your axles to a more appropriate ratio once you figure out what size tires you'll want to run once you determine how big of a lift you want. The taller the lift, the more it costs since the taller the suspension the more that needs to be done besides just installing taller springs and shocks.

What is your budget? That will be a big part of your decision.

Lastly, and quite seriously, please get rid of that K&N air filter. It is well known as a very poor air filter that passes WAY more harmful dust and air into your engine than you ever knew possible when reading about how much power it adds... and it literally adds zero power since the TJ's factory air intake is literally not restrictive in the least. It can easily pass more air than the engine can consume. And the C part of the CAI is no happening since it's sucking in the hot air inside the engine compartment. Then you can also remove the throttle body spacer as it is doing nothing but spacing the throttle body up. Spacers can perform wonders when placed under carburetors and the first generation of throttle bodies that had a fuel injector in them.... both of those pass "wet" air/fuel through them and spacers can and do help with them. But with later generations of throttle bodies like our TJs use, they pass ONLY air through them. Adding a spacer under a modern throttle body does literally nothing other than give the air a longer path which doesn't do a thing. Use it for a paperweight where it will actually do something.

And lastly, do you have any particular types of trail types you want to do there? I would imagine Montana has some pretty awesome back country to explore!! Your local trail types will influence the recommendations the forum's members will offer. :)
 
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First, a big welcome to WTF which is a great forum that is very technically astute! The next is to start saving to regear your axles to a more appropriate ratio once you figure out what size tires you'll want to run once you determine how big of a lift you want. The taller the lift, the more it costs since the taller the suspension the more that needs to be done besides just installing taller springs and shocks.

What is your budget? That will be a big part of your decision.

Lastly, and quite seriously, please get rid of that K&N air filter. It is well known as a very poor air filter that passes WAY more harmful dust and air into your engine than you ever knew possible when reading about how much power it adds... and it literally adds zero power since the TJ's factory air intake is literally not restrictive in the least. It can easily pass more air than the engine can consume. And the C part of the CAI is no happening since it's sucking in the hot air inside the engine compartment. Then you can also remove the throttle body spacer as it is doing nothing but spacing the throttle body up. Spacers can perform wonders when placed under carburetors and the first generation of throttle bodies that had a fuel injector in them.... both of those pass "wet" air/fuel through them and spacers can and do help with them. But with later generations of throttle bodies like our TJs use, they pass ONLY air through them. Adding a spacer under a modern throttle body does literally nothing other than give the air a longer path which doesn't do a thing. Use it for a paperweight where it will actually do something.

And lastly, do you have any particular types of trail types you want to do there? I would imagine Montana has some pretty awesome back country to explore!! Your local trail types will influence the recommendations the forum's members will offer. :)
Thanks for the feedback! Was looking to spend $1,000 for the lift, outside of other modifications and tires.

Trails vary as much as the state, but really its to get into prime mountain hunting country during the fall/winter/spring.
 
Proper gearing never hurt anyone. Go the easy route and find a pair of axles from a 4cyl. Should cost less than $500, likely closer to $300.
that’ll get you 4.10’s then lift as you see fit. We all have our preferances
Great idea! I'll add that to my junkyard list, of which currently contains a hard top and wheels :)
 
To keep ride quality and run 32’s I do a 1” or 1.25” body lift and a 1/2” bump stop spacer with some Rancho 5000x shocks and call it good. Unless you want to move the frame up for clearance. There again I’d leave the suspension along and do a mild tummy tuck