I am in the process of building my 2 door 2016 Rubi from stock. So far so good. After the Teraflex ST3 lift with fox shocks and Cooper STT Pro 37/13.50/17 with Pro Comp wheels ( -6 offset or 4.75 on backspace) it drove like a dream except off road in full lock turn rubbed on the shock reservoir and lower arms. Also had to bring the rear axle back but that has been done. My mechanic got some 1.5 inch spacers from 4 wheel parts installed. I absolutely hate them. Drove about 200 miles this weekend, most pavement and about 35 miles dirt. Off road good. On road some steering wandering and some notable rougher ride, general vibration. Had Jeep up to 80 mph, from 55-60 and up no difference unless I hit a very smooth new section of interstate. Alignment was done once the lift and new tires were on, and as I changed gearing drove the 500-600 miles then had it back in for retorquing and check on everything, including tires.
Suggestions?? Will be back at mechanic this week to let him look at alignment. I am also sourcing wheels with a greater offset -- found some with a -18 or 4.29 that are not beadlocked, but bloody expensive. The reservoirs will likely have to be moved. Any help would be appreciated.

 

The general suggestions for net backspace are 4.5" for 35"s, and 3.5" for 37's. As you have found, there aren't too many non-beadlock rims with that low of a backspace, so, beadlocks and adapters are common.

But I would be curious to see what your alignment specs are. When I went to 37's and added 1.5" Spidertrax to the 4.5" bs rims (net of 3.0" bs) I did not notice any driveability change like you are describing. No extra vibrations or rougher ride or different in-lane tracking or anything like that. Just a wider stance. So, post the numbers if you got em. What psi are you running? (was it changed when the adapters went on?) Have the tires been re-balanced/rotated? (sounds like the only change was the adapters, but still worth asking.)

 

Not sure on the alignment specs, my mechanic has been working on 4x4's here in Az for 30 + years so should know his stuff, he thinks perhaps the steering knuckles might be under some pressure too. I am running 28 lbs for the Coopers that seem to be good for on pavement, and that has not changed since I had them installed. Of course hotter than hades here some days so the air pressure can vary and will have to adjust once it cools off. Once I see him this week I will get the specs and post them.

The best I can describe is it now rides like my old 92 YJ did when I had full pressure in the tires, hit a bump or pothole, or cross over a ridge on the pavement and the whole thing shudders. Well, maybe not quite that bad.

 

This sounds like a bad steering joint to me, and unrelated to the spacer. I agree with nthinuf above......I've run as low as a net 3.0" BS previously (4.5" BS wheels with a 1.5" spacer). You should notice no difference in driving with or without the spacer. What do you have in regards to steering components? Have you upgraded everything up front?

In general though, y, you'd be better off having proper BS wheels, and the non-beadlock options are limited. I know Dirty Life has some that are 3.5" BS and can be mounted traditionally or, with an added ring, as beadlocks. I'm not certain about other brands.

 

Only upgrade to steering was a fox steering stabilizer was installed when the spacers went on. And an adjustable rear control arm from Teraflex that brought the pinon angle down and pushed the rear axle back, which was needed as when flexing rear tires were up in the front of the rear fender well.
It drove great prior to the last upgrades; after the lift, install of a rear Currie anti rock, and tires and wheels, and 5:13 gears. I was impressed with how well the vehicle handled curves, and how smooth it drove, for a Jeep. Very responsive and solid steering. I guess the above comparison to my old YJ is unfair, but it really does handle like a different vehicle, and one with more vibration to the ride. Off road it seems good, just figuring out it's radius on things. Fun this weekend topping out on an old mountain road and seeing the ATV people looking at me like " how did a Jeep get up here?!"
Also the braking seems completely adequate for the way I drive. Another thing is perhaps one of the spacers is not good?? Machining might be off??

 

It sounds like a lot of recent changes. I'm not implying this is definitely your issues, but when adding bigger tires, the factory joints take a beating, especially with 37s. If you're using a quality spacer like a spidertrax or even synergy, it's unlikely to have poor machining. Also, if that was the case, I'd suspect the combo would be so out of balance at interstate speeds you'd know it was a balance-type issue.

You could remove those spacers and take it for a spin to see if it's any different. Free to do cept the time waste. I know you might be thinking "well, i already know what it was like before spacers", but that doesn't necessarily mean that you blew a joint or something between that time. Separately, if you haven't upgraded your ball joints, you need to with 37s. Ticking time bomb, so at least start budgetting and reading up on that.

 

Yes, planning on upgrading ball joints looking at Dynatrax for that, since they can be rebuilt. Hope to get some time out of the stock ones though but I know to expect that within the year at least. Will be dropping by mechanic on Wednesday will know more then.

 

I would suggest not to bother with this. Here is my experience and why I'd steer you away.

https://www.jk-forum.com/forums/modi...ebuild-347721/

Rare Parts is what you're after, or take chances with Teraflex.

 

The verdict--- the fox 2.0 steering stab responsible for 90% of the drive issues. Shop too busy to get it on the machine for alignment but they pulled the stabilizer off and I drove on interstate--no wander, no fighting the steering. Looking at tire wear will drop air pressure to about 25 lbs, may have to turn off TPMS, I think with AEV Procal I have it at 24 lbs which I think is the lowest setting I saw. Will have to check that. So have no stab in right now since the stock one got thrown away but will get something in there before I go wheeling again. So no problems with the spacers apparently.

Thanks for links on ball joints. Teraflex products I have been very happy with but bookmarked the Rare Parts too.

 

I don't recall you mentioning that SS before. You definitely don't want some strong gas-charged unit there. Think about just compressing a gas-charged shock. Those things are constantly trying to extend with some real force. If you think about that sitting parallel with your axle, it is constantly pushing your TR one direction. If you want a SS, the cheapest things work great. Something with near equal resistance both extending or collapsing. This is one of those things the factory unit is great. The Teraflex VSS9550 is good too. If your jeep is set up properly, you're fine without as well. Just keep an eye on your BJs, cuz if you're using that jeep off road, the factory don't tend to last long with 37s as I mentioned. Bad BJs don't tend to disguise themselves very well so I'm sure you'll see/feel the signs when it's time.