sua vs. soa (1 Viewer)

[Mozzio]

After 20 years i finally got another 40. Mid life crisis-who knows?
Been reading all the posts for a few months and have learned more than I thought possible. I have seen spring under and spring over mentioned quite alot and am hoping someone can help explain the benefits and drawbacks of each. tried doing a search but did not find much. btw my truck is a 1966 fj40 that is mostly stock. Small lift and tires only.

 

[dmaddox]

stay spring under. why?

cost
steering
cost
welding
cost
driveability
cost
measuring 5 million times
cost
send me a PM - I have pictures of the whole project.

It also depends on what YOU want to do with the rig. If you want it to turn into a weekend rock warrior - soa. Want to stay practical, have everything line up and work as Toyota intended it to - being able to drive it every day getting the same gas milage and ride as you have now. - sua.

Having done it all - I am biased. A 4" lift with ARB's can work wonders....

I dunno....

Ragman

 

[Poser]

Hit the Tech Links and read away.....

 

[Josie'sLandCruiser]

Hi All:

I can think of a *ton* of upgrades one could do to a 1966 FJ40; the spring-over is pretty far down the list. The only reason to pull the SOA swap up the list a bit would be if the rig was being built for very hard trails.

Where do I start?

1) Upgrade to a 1969 or newer rearend (fine spline axles);
2) Upgrade to 1976 or newer frontend (fine spline axles & disc brakes);
3) Install a brake booster;
4) Install power steering;

For off-road use larger, aggressive tread (read: mud terrain) tires and a locking differential in the rearend. Oh, and a full roll cage!

Regards,

Alan

 

[F-junker]

I would start with power steering, then front brakes and power booster. These truck w/o power steering are a handful when moving slowly. Then do your other upgrades when time and money afford it.

 

[Adventure Teq]

I'd agree with the upgrades first.


SOA:
Super flexy
Keep the original springs
About 5 to 6 inches of lift from it
Much harder (costly) to do correctly than slapping on a lift kit
Requires steering mods (crossover, hysteer) $
Cut and turn of the front axle knuckles in order to get proper pinion angle and maitain proper steering caster $-TIME-$
Trac bar isn't a bad idea either $$
Should use new driveshafts with CVs at the Tcase ends once you get the pinion angles set. $$$$
Extended brake lines $

But if you like building s***, working on your truck, and have money then these are all big s.

SUA:
Easier to install
Minimum other parts needed i.e. caster shims etc.
Only get 4 inches at most
Stiffer ride than older original springs

In summary, if you rarely go offroading than a SOA is not worth it. If you do go often and are willing to head down the road of many mods in the future then it's a great way to start. If you mostly drive around town and occasionally hit the trail then a lift kit is prolly best.

Good luck.

 

[green73]

PAY ATTENTION HERE!! Alot of good info from those that posted before me. I am SOA, and have wheeled with 4-link, SOA, and SUA guys. I am continually impresses with how good a well done SUA rig does with lockers. Pay heed to the info on power steering and disc brakes. That is money well spent in conjunction with a SUA or SOA whatever you choose. The hidden costs of an SOA on a cruiser are much different than with a J*^p, especially in the steering department. With SOA you will also need an anti wrap/trac bar or axle wrap and snapped pinions/bent springs are in your future. Properly fabricated, an SOA costs eventually match or pass a lift kit. So, Hy-Steer and Wrap bar adds a bit to the cost. Moving the shock mounts, shacke reversal (Optional), cut ad turn (IMO Optional), shocks themselves... If I had it to do over again, I would have stayed SUA for a while longer and kept my stock springs to do an SOA at a later date. Not to discourage you from doing an SOA, but all things need to be concidered with the SOA option. Research here is your friend, which you appear to be doing.

SUA, re-gear to match the tire size and a locker (your preference which axel) will get you further on the trail than you might think possible. Hell, Mark Algasey (yeah I know I spelled it wrong) did the waterfall trail at Katemcy in a stock FJ45LWB pickup, 3 ON THE TREE!

TO reiterate. Bigger tires will most assuredly necessitate power steering, and disc brakes. I would put these items on top of your list. Make the choice that's best for you.

 

[Adventure Teq]

Hell, Mark Algasey (yeah I know I spelled it wrong) did the waterfall trail at Katemcy in a stock FJ45LWB pickup, 3 ON THE TREE!

You mean dis Mark Algazy on deez waterfalls?

My 2 1/2" SUA 40 on 32s with open diffs handled the trail quite nicely too. A locker would have surely made it easier. Coming down is one thing, going up is a different animal.

 

[camcruiser13]

SOA baby

 

[Mace]

You can get a SUA 8" lift...

 

[pbgbottle]

SAY THAT AGAIN

SOA baby

 

[Dennis@Moab]

I went soa last year and no regreats, but it took me a couple of years to get the parts together. DENNIS

 

[Adventure Teq]

You can get a SUA 8" lift...

You kidding? Where?

 

[camcruiser13]

SOA baby

 

[fj40charles]

I prefer a SUA for side hill stability. Many SOA rigs are just too tall and does not feel secure on side hills. Nothing wrong with SUA or SOA. Just need to decide what you want to do with your rig. I perfer a 4 link, but that ia another discussion.

 

[Trollhole]

After 20 years i finally got another 40. Mid life crisis-who knows?
Been reading all the posts for a few months and have learned more than I thought possible. I have seen spring under and spring over mentioned quite alot and am hoping someone can help explain the benefits and drawbacks of each. tried doing a search but did not find much. btw my truck is a 1966 fj40 that is mostly stock. Small lift and tires only.

You have the Ball and Claw front axle? That will need to be addressed before anything else. Which means a new front end. And when this happens you will want a disk brake front end since it is a much better upgrade.

If you want cheap and don't want to spen the time to do it right then get a course splined front end. (people are basically giving these away) keep your drum brakes. Buy a cheap 4 inch lift. This will be close to a SOA as you can get. Buy some cheap shocks. and have about half a dozen spare birfs on hand. With course splined birfs and 35s or greater it's not if it's when if you plan on doing anything difficult offroad. Though if you just plan on some light wheeling and around the town vehicle then you will be just fine.

Or if you want really cheap. Get a set of long shackles, some castor shims and some 33's and be done with it.

 

[Trollhole]

SOA is meant for bigger tires. BAll and Claw and course splined birf were not. Though one is way better than the other.

 

[Mozzio]

Now I have way too much info.
I am looking at the faq's to see what I need for power steering and disc brakes.
Both projects seem to be way over my abilities though.
I will have to find someone with the mechanical ability to help with guidance so I don,t screw things up. I take steering and braking a little to seriously.
Thanks to all for the input.

 

[Adventure Teq]

Don't forget the tech links at the top also. Excellent SOA writeups and others as well.

 

[camcruiser13]

hawk heres your 2' lift, pretty sweet i think you should do it.