Jeep Cj5 Tire Size Upgrade Advice. Help!!

Some pics and more info might help (v8?, transmission, gearing)...A 77 cj5 is a late model, and is a bit more tolerant of lifts and already has quite a few improvements in terms of steering, braking etc. as well as lots of aftermarket support for things like new lift springs, body mount lifts, or shackle lifts. Depending on where and how the jeep sits now, one route might be better than another. Most of us will suggest lift kit from BDS - for the late model cj5 I think its called a 4" lift and will clear 33x12.5 - you might even be able to squeeze 35x12.5 if you add a slightly longer shackle (a lot of us here clear 33s on early cj5 models using their 2.5" lift kit with a slightly longer shackle). Skyjacker also makes a 4" kit that might work well. If you already have a bit of a lift, and are budget limited, you might be able to get the clearance using some other routes like just adding slightly longer shackles or body lift etc - this would probably get you to 33s, but no more. One big thing to consider with jumping up tire sizes on later jeeps is the axle gearing...later jeeps often have higher (numerically lower) gearing that starts to feel very sluggish when the tire size gets big....guessing you can run 33s without too much issue, but 35s I think would be too much to enjoy driving it.

and now the disclaimer... most of us will caution against getting to aggressive with lift and tire size as these short wheelbase jeeps can get a bit tricky with handling and highway driving. And as these old jeeps are old (44+ yeas old in your case) most of us will suggest making sure all the necessary systems (like braking, steering, drivetrain etc) all are in good working order before getting into the modifications like lifts etc...and finally, if off-road capability is the goal, a cj on 31s can keep up with modern jeeps and whatnot on 35s on hardcore trails. If appearance is more the goal, there are budget ways to get where you want, but will come with trade-offs with driveablility.

 

I think Toyo also makes a 33x10.5R15 - I think Doug just bought a set.
https://www.4wheelparts.com/p/toyo-...6B8yiHrEo6vuNA_9lrtV6K2pjZYft2mwaAsLcEALw_wcB

Although I personally like a tall skinnier tire (and I think quite a few on this forum also like the look), its certainly not everyone's preference, and it seems like the OP is interested in a wider tire. I've seen some nice later cj5s (with the longer 84" wheelbase) that run 35s quite nicely (including some from members of this forum)- although many of them are SOA, and that is not a trivial modification.