i have a 1971 jf40 and im starting to do a spring over. i have every thing off all i need to do is take the axle off the leafes and weld new mounts but i need to know if i really need to cut the axle and twist it so i dont have a step drive line. or does that matter. i hope you guys get what im trying to say. just hope you can tell me what im looking for.
Do a search for cut & turn axles and read all the debate over this. Then make your decision. I personally, if I had to do it again, would have not c&t and not have done the shackle reversal. Just welded the perches on with the right amount of caster, and had my driveshaft extended. But everyone has done this part of the SOA different. The c&t, and the shackle reversal are two things everyone argues over with a SOA.
Just 3 link the front and 4 link the rear and be done with it.
Do a search for cut & turn axles and read all the debate over this. Then make your decision. I personally, if I had to do it again, would have not c&t and not have done the shackle reversal. Just welded the perches on with the right amount of caster, and had my driveshaft extended. But everyone has done this part of the SOA different. The c&t, and the shackle reversal are two things everyone argues over with a SOA.
Just 3 link the front and 4 link the rear and be done with it.
Nope, not at all. If anything the cut and turn will lessen the gear oil the pinion bearing gets. The big issue is driveshaft angle, especially if you do a SR and you have a stock length drivetrain.
the major issue is not driveshaft angle, but driveshaft binding. Depending on your setup. You may or may not have an issue. But I would be suprised if you did not...
the major issue is not driveshaft angle, but driveshaft binding. Depending on your setup. You may or may not have an issue. But I would be suprised if you did not...
You can't change the perches from the factory position without affecting caster either positively of negatively unless you also cut and turn the knuckles. I would only run positive caster but no where near 6 or 7 degrees, 3 is good. I have run negative caster and the spooky wandering steering was super scary.
My take-On an FJ40, with it's very short drivelines, a cut and turn is a good idea. Point the pinion exactly at the t-case flange, and rotate the knuckles to the correct caster. That is really the optimum set up.
I would not do a shackle reversal again, though once done, it drives fine. The SR will require a longer slip drive shaft, which will add $200 to your build costs.
I don't dislike the driving characteristics of the sr, just the extra cost, and the flipped springs caused clearance problems with my 4x4labs high steer. All that could have been fixed if i hadn't done a SR.
In my oppinion if you need extra wheel base, then extend the frame and move everything forward. But that's a little off topic.
The c&t at 3 degrees of caster and the sr with powersteering drives and tracks great. The cost of the turn, $150, and the cost of the long slip, extra $200, plus all the fabrication wasn't worth it for me. But to each there own.
I guess it is nice haveing the pinion aim a little higher for rock clearance, but the 38"s help with that more so.
If you flip the springs to lengthen the wheelbase you don't need to CT. The longer wheelbase also helps drivability issues.
Get the steering arm from Aqualu. Use the Dodge spring perches and the ford shock tower. That's the best and lowest budget solution.
i have a 1971 jf40 and im starting to do a spring over. i have every thing off all i need to do is take the axle off the leafes and weld new mounts but i need to know if i really need to cut the axle and twist it so i dont have a step drive line. or does that matter. i hope you guys get what im trying to say. just hope you can tell me what im looking for.
A lot of guys have done it with out the cut and turn. If it is strictly a trail rig you might be alright skipping the cut and turn (I wouldn't) but if it is going to be used on roads I would do the cut and turn and have it welded by a certified trustworthy welder. If not for safety than at least for a better drive down the road. I don't think you will find any of the experienced cruiser mechanics who will tell you it is fine to skip the cut and turn.
I'll stand by that. You can do an SOA with no C&T by extending the wheelbase. It works great and it is my preferred approach. I've lost count of how many SOAs I have done, but it's counted in the dozens. I've only C&T'd a couple of '40s. I consider a C&T a requirement on '55s and early vintage '60s. I prefer it on later '60s. I can go either way on the '62s.
With the '40s, if you don't extend the wheelbase then you need to do a C&T. If you extend it, normally you don't. If you do a V8 swap and move the tranny forward significantly you might still need a C&T. Depends on your individual setup. If you move the V8 forward to allow the addition of an extra T/C, then you almost certainly will not need a C&T.
I've seen people advocating a C&T in order to increase the caster over stock. In some cases this seems to me to just be an attempt to justify a C&T as a requirement in internet discussions. I, and all of my friends/customers who are driving non-C&T '40s, have had no dissatisfaction with the steering with stock caster. Make sure the rest of your steering and suspension is right and I doubt that you will either.
I'll stand by that. You can do an SOA with no C&T by extending the wheelbase. It works great and it is my preferred approach. I've lost count of how many SOAs I have done, but it's counted in the dozens. I've only C&T'd a couple of '40s. I consider a C&T a requirement on '55s and early vintage '60s. I prefer it on later '60s. I can go either way on the '62s.
With the '40s, if you don't extend the wheelbase then you need to do a C&T. If you extend it, normally you don't. If you do a V8 swap and move the tranny forward significantly you might still need a C&T. Depends on your individual setup. If you move the V8 forward to allow the addition of an extra T/C, then you almost certainly will not need a C&T. Mark...
Mark, what about a 45 troopy? I have an 81 and have already put a 2.5" lift on it, but I want to go bigger. Would you need to C&T or is the wheelbase long enough you don't have to worry about it?
