Need Driveshaft advice. Double cardan or not?

[lorenzo816]

Need some advice here on pitching the 14 up and possibly doing a double cardan at the Tcase output end of the shaft OR keeping the shaft “standard” and matching the pinion angle to the Tcase output.

So I’m switching rear axles from a fzj80 land cruiser to a 14 bolt. The LC is offset to the right.
My Tcase output is a flanged 1310 to a high angle 1310 flange which has the LC bolt pattern.
The 14b is centered so it may fix my issue but wanted experienced opinions here.

The problem I’m currently having is I eat through the upper u-joint IMO too often. The trans mount and engine mounts have been replaced to eliminate that as a culprit but I still ate through another u-joint earlier this year. I’m replacing the front joint maybe once every year.
I’d say the truck is 80/20 offroad and street. I can do 70mph but most the time it’s just regular roads max 55. The truck literally doesn’t go more than 500-1000 miles a year!

Olivers built the shaft and they’re balanced. I think the constant rotation to the right for the offset is killing the front ujoint. I’m wondering if simply centering the rear with the 14 b fixes the joint-eatin problem or should I take the opportunity to pitch the pinion angle up.

With the current LC rear::
The length of the rear shaft from flange to flange is roughly 4’
From joint to joint is roughly 44”
The angle of the shaft is 19°

With the 14b, the yoke looks to be in the same spot as the LC flange which makes the “future” joint to joint shaft length longer by 1” or 2.

Thoughts please.

 

[PAE]

How often did you lube the u joints on joints that failed ?

 

[lorenzo816]

Good question. I didn’t buy a replacement greaseable uJoint for the front after the first failure. The first failure was a greasable joint and it took out the yoke ears the first time on the highway after a 3 day wheeling weekend.

I’d have to service disassemble the joint caps what not in order to grease these.

 

[Etyler2]

Creek crossings, bad angles, do you grease them every trip?

 

[ScottRS]

I'm confused.
What I'm maybe getting:
T-case is centered?
Front u-joint is 1310.
Rear u-joint is Toyota?
Front u-joint is not greasable.
Rear u-joint is maybe greasable?

What transfer case are we talking about here? Is it level or angled down?

If you're running non greasable 1310s at 19 degrees, good on ya for getting them to last 1k miles.

14b you will likely be going to 1350 on that end whether you like it or not, unless you spend on a flange or alternate yoke.

What are your projected shaft angles (vertical, lateral, and total) with the 14b? Will you still have lateral angle or will it be straight on? You can't cancel lateral with a double cardan on one end, best case you'll have a small vibration and the 1350 will take it, but it may move your joint eating to the other end.

Also keep in mind the 14b pinion is lower than the LC pinion from axle centerline. Not a lot, but some.

 

[bdkw1]

^^^^^ with lateral offset, a cardan will make vibes worse. What is the offset difference?

 

[94toytruck]

I've been running the same Toyota double cardian at my case for years with a Toyota joint at my 14 bolt. I had a 1350 on the 14b before and would break it like once a year.

 

[lorenzo816]

First, thanks for the questions and feedback.

No no deep creek crossings maybe the occasional mud hole but rare.

The tcase is centered. 0° give or take. The fzj80 pinion is maybe 5” to the right of center and maybe 1-2° up.
Both joints are 1310 and non greaseable.
The LC end has a high angle flange.

I plan on going to 1410 on the 14b end.
iirc that’s what’s on it now. I’ll measure to be certain it regardless - I’ll still go 1410 for the angle rotation and strength benefit.
The 14 is way more centered compared to the LC.
I’ll go measure in just a bit but yea probably off to the right maybe an 1” maybe

 

[lorenzo816]

I've been running the same Toyota double cardian at my case for years with a Toyota joint at my 14 bolt. I had a 1350 on the 14b before and would break it like once a year.

Is your rear 14b pitched up to the case?

I measured the offset of the current LC rear, it’s closer to 6-7” to the right and the 14b is probably an inch. So way more center comparitvey.

I may also see if I can get a 1410 flange that matches the current Tcase output, thay way both ends are stronger and have good rotation angle possibility. Dunno if exists or need a custom spacer made up.

I just don’t want my issue to come back. IMO eating joints once a year (500 ish miles) is too frequent. Either it’s a strength issue overall or it’s a combination strength and offset issue.
So when the new axle centers the rear, do yall think that will Solve my problem? Or pitch the pinion up and DC the Tcase end??

 

[94toytruck]

My 14b points directly at the case.

I vote ditch the 1310 and move to a bigger joint with a DC at the case.

 

[lorenzo816]

My 14b points directly at the case.

I vote ditch the 1310 and move to a bigger joint with a DC at the case.

What’s your driveshaft angle and length? And have you had any front pinion oiling issues?

 

[94toytruck]

I honestly would have to look, shaft is stock length IFS Toy mini truck front retubed with .250 wall so it's short. Full droop without limit straps the DC is near maxed full stuff I think the pinion is level with the case output possibly above by a bit.

 

[ScottRS]

Are you sure about the length/angle? 19deg at 44" center to center is over 14" of total offset (in whatever direction), is that at ride height or extreme edge of travel envelope? That seems like a lot if it's at ride height. Can you separate the up angle from the side angle (or just tape measure it) and give us those numbers? And measure the 14b pinion center vs dimensional center while you're at it, they aren't centered either.

I would check your centering, if the 14b pinion is within an inch or so of centered on the rear output, I'd DC it and point it at the case. If it's more than 2" off, I'd be concerned about it.

If you want to spend and can't make the angles work you can get a DC-DC shaft built, but it'll be spendy and your driveshaft guy will think you're pushing your luck on the crazy-dumb line.

 

[lorenzo816]

94toytruck yea when ya get a chance please look. I have time. Haven’t got the 14 geared yet. Then I’m going to weld spring perches after that.

ScottRS here is a pic at ride height.
Yea it’s tall ish but it works and i honestly don’t have vibe. I just have chatter at 55-65 on coast.
You can also see I have wrap bar too.

 

[YotaAtieToo]

Literally just drove my 81 Toyota ~25 miles at 60 mph, no real vibes (other than being a beater) it's a centered tcase, that been raised, ~40" driveshaft and Fzj80 rear. Even has the shitty 1st gen cv on top.

The ujoint isn't as smart as you think, it doesn't know left or right from up and down. Only angle.

1310s are a joke, I don't understand why some driveline places will sell you on expensive conversion flanges to switch over to a weaker joint. Many, including Jess at high angle, hold the Toyota joint equal to a 1350, but much easier to get more angle from.


To answer the original question, put a cv on. Not that a single joint won't work, but it's just so much nicer to have the pinion tipped up away from rocks. If you're staying leafs, I like to go ~2* lower than perfectly at the pinion. That way when you're pulling a grade and the axle wraps a little, you're in the right spot and not past.

Edit: just saw the wrap bar, so maybe that's bad advice.

 

[lorenzo816]

YotaAtieToo so you have an offset fzj80 rear or did you center it up?
Is your pinion angle and tcase output same degree? Or did I read that incorrectly and you have a double cardan output and you’re pitched up in the rear?

I plan to run a wrap bar when all is said and done on the 14 bolt. Just need to figure out driveshaft formula and spring perch for pinion angle.

I do agree the 1310 is just not strong as everything else. I just used what the flanges mated to and built from there
I’m sure we’ve all seen this before.
I do appreciate the advice from everyone.

 

[YotaAtieToo]

YotaAtieToo so you have an offset fzj80 rear or did you center it up?
Is your pinion angle and tcase output same degree? Or did I read that incorrectly and you have a double cardan output and you’re pitched up in the rear?

It's a stock rear, so still offset. Pinion is tipped up, but the joint obviously still has angle because the diff offset. It's not "right" but still works.

Don't mind the shock

I plan to run a wrap bar when all is said and done on the 14 bolt. Just need to figure out driveshaft formula and spring perch for pinion angle.

I do agree the 1310 is just not strong as everything else. I just used what the flanges mated to and built from there
I’m sure we’ve all seen this before.
I do appreciate the advice from everyone

I get if you already have the flanges or whatever. I assumed you were all Toyota. I've seen other guys convert Toyotas to 1310, which is a total waste of money, imo.

 

[lorenzo816]

Ah okay thanks for the pic!
Looking at yours super similar to my current setup, I should’ve pitched my pinion from the beginning and ran double cardan.
Well that’s the solution for the current setup,

My new dilemma is the 14bolt shaft length and angle.
I have a friend with a similar setup but he’s on 35s. I’ve got 37s.
I’ll get him to measure and compare. I know my shaft length is absurd long. One day I’ll change to a dana 300 case but one huge step at a time.

 

[Winchested]

Just point it up and go with a DC and be done with it.

Right now your angles are not equal and opposite which is killing the joints.

I've got 3 good hard wheeling trips on 1310 joints (DC) on tons and 40s and haven't hurt one yet. But angles are correct for DC shafts.

And I've put Bout 3500 km driving on it this summer too.

 

[lorenzo816]

Winchested would love to see that super scout. I have a ‘71 810 myself!

Yea so you’re saying for the 14 b just pitch it and double cardan it?
Keep in mind I’m not trying to solve the current offset land cruise axle which is going bye bye very soon!

 

[ScottRS]

There's a fairly common 1350 series non-high-angle DC out there, does about 28deg at limit, but it's road friendly. Get that, adapt it to whatever toy minitruck variant transfer case flange you have, get the other end set up for 1350 or 1410 (whatever you like), tip the pinion at the t-case, weld up the spring perches and wrap bar to match, and hammer down. It'll be a near carbon copy of what I have in the back of my Jeep, and unless your 14b has been narrowed, it'll be close enough to center to work nicely.

 

[Winchested]

Winchested would love to see that super scout. I have a ‘71 810 myself!

Yea so you’re saying for the 14 b just pitch it and double cardan it?
Keep in mind I’m not trying to solve the current offset lane cruise axle which is going bye bye very soon!

Yes that's what I would do. I've got a 1310/1350 conversion joint on the 14 bolt right now, once the engine swap is done going to 1350s at both ends Double cardan.

Check out my build thread.

 

[smracing]

I run the offset fj80 rear with the pinion pointed at the tcase. DC shaft, no issues at all.

 

[chaplinfj60]

i had similar issue, should have went double card but went toyota at tcase with toyota slip and 1410 at axle. got the parts from drive shaft parts. and we adapted it all to work. 1/4 wall maybe thicker cant remember.

 

[chaplinfj60]

no street riding for me, but you could use the double at tcase and 1410 and have crazy angles for sure. just ideas

 

[lorenzo816]

Appreciate all the input here. When I get the 14 geared and locked, I’ll be ready to roll it under the truck to weld perches and shock mounts. Then I’ll have final “new” measurements at ride height to work with. I’m still leaning towards pitching the 14 up and DC behind the case. I could keep the 1350 that’s on the 14 yoke now because it wouldn’t see the extreme angles. That’s the tentative plan at least. Keeps the pinion and guard from becoming a shovel.
I’ll post up once I get going

Oh and any of y’all want the land cruiser 80 axle stuff, let me know.

 

[lorenzo816]

Update.

I eventually sold all of the Land Cruiser stuff. Helped pay for all the 14 bolt stuff.
I finally got room back in the garage for two vehicles and cut the fzj80 axle free. No turning back now.
This pic is not quite ride height but I did set it at ride height shortly after this pic.
I’m seeing about 15° pinion angle on new leaves. I haven’t burned in the spring perches yet.
Some folks say tilt it down 1-2° for wrap. I hope to get my wrap bar fabd on there eventually. You can actually see it on the floor in the pic.
I found a flimsy pvc tube to use for visual aid.

Any Thoughts before I burn it in?

smracing whats your angle?

 

[lorenzo816]

Well i burned it in over the weekend.
The case was down 1° so I settled around 13-14° up.

I'll post up the drivehsaft when I get there.