Driveline angle question

tonkota · 12-20-06, 06:06 PM

I am putting a 350/SM465/NP205 into a 1973 FJ55.

Everything is "in" and clamped in place and I have clearance where I need it.

The question I have is how critical is it that I have the driveline flanges parallel to each other?

I have one CV for the front shaft, do I need one for the rear also?

projektdotnet · 12-20-06, 08:50 PM

I don't have the CV rear and I wish I did

it rattles bad at low speeds and is just flat out LOUD when on the freeway and coming off the gas. I've heard it's not good for the T/C either.

Mark W · 12-20-06, 10:33 PM

It is very important to have the flanges parallel. You have to. Only way not to is to use a double carden joint at the T/C end and point the pinion flange at the T/C so that there is virtually no deflection at the diff Ujoint. Either way you have to have the angles set to a specific relationship. You can't run mismatched angles with ujoints at each end and you can't run just any old angles with a double carden either.

Mark...

sine80 · 12-20-06, 10:37 PM

if you dont have cv's, the angles have to be the same. I did cv's at both ends and Im glad I did, seems to run fine and I have no issues with dl vibration. I pick them up for $25 each, they wernt too expensive.

2damslow · 12-21-06, 05:09 AM

I think you'll have far more problems with the centered rear 205 going into the offset axle. Everything else is just minute angle differences. The setup can withstand small differences with not being parallel because the axles on leafs are dynamic, but the angle between a centered tcase to an offset rear is a static setup. The error will always be there.

tonkota · 12-21-06, 09:06 AM

Thanks guys. This is what I was thinking and I just needed to be sure.

The offset rear isn't a big problem. As long as the flanges are parallel, the drop and offset are just angles.

Question 2:
the front drive shaft that I have has 2 u-joints at the t-case. this is the CV or is it a "double carden"?
Question 3:
Can I get a double u-joint setup for the rear output of the NP205? It does not have a flange (like I am used to) it just has a yoke that attaches to the u-joint caps.

Thanks!!

tonkota · 12-22-06, 08:45 AM

No more help?

Pin_Head · 12-22-06, 09:36 AM

Quote:

Originally Posted by tonkota

The offset rear isn't a big problem. As long as the flanges are parallel, the drop and offset are just angles.

That is correct (for a basic 2 U joing shaft). Toyota used a centered diff with a offset transfer case on early FJ40s, so being offset is not an issue if the overall angle does not exceed the limit and the flanges are parallel.

Quote:

Originally Posted by tonkota

Question 2:
the front drive shaft that I have has 2 u-joints at the t-case. this is the CV or is it a "double carden"?
!!

Yes.

Quote:

Originally Posted by tonkota

Question 3:
Can I get a double u-joint setup for the rear output of the NP205?
Thanks!!

Yes, but then you would need to have a centered diff to match the transfer as CV drivelines do not permit any angle at the differential between the driveshaft and pinion (unless you have a CV joint at each end).

tonkota · 12-22-06, 11:49 AM

OK. I will pay more attention to the rear driveline alignment.

Just to be sure, a driveline with two u-joints is called either a double carden or a CV?

Mark W · 12-22-06, 12:27 PM

A "CV" is a "constant velocity" joint. A double carden is a type of constant velocity joint. (So is a Birfield).

A CV delivers power smoothly, without the pulsing that a Ujoint creates. This pulsing is why Ujoint angled have to be matched and why they have to be in phase in order to eliminate the pulsing and not cause vibration.

For a driveshaft under a Cruiser, the type of CV joint that you use (if you use one) is a Double Carden.

Mark...

tonkota · 12-22-06, 01:09 PM

OK. Makes sense. I knew a birf was a CV.

What sort of tools should I use to ensure that the drivelines are exactly where I need them? Tape measure, speed square, angle finder, and BFH? What else?

Pin_Head · 12-22-06, 03:04 PM

Quote:

Originally Posted by tonkota

Just to be sure, a driveline with two u-joints is called either a double carden or a CV?

A drive shaft that has two U joints in a single yoke at the end is called a DOUBLE CARDAN joint.

Mark W · 12-22-06, 11:56 PM

Quote:

Originally Posted by tonkota

OK. Makes sense. I knew a birf was a CV.

What sort of tools should I use to ensure that the drivelines are exactly where I need them? Tape measure, speed square, angle finder, and BFH? What else?

I use a medium-high quality bubble level with a marked and adjustable dial. This lets me interpolate to about half a degree or so. This allows me to set the flanges to match.

Mark...

sine80 · 12-23-06, 12:07 AM

cv or double carden is on the left.

Pin_Head · 12-23-06, 09:42 AM

I don't know if you have seen this, but here is a little light reading about driveshaft types and geometries and why you need the angles a particular way.

http://www.4xshaft.com/driveline101.html

tonkota · 12-23-06, 10:11 AM

Very good drivelne writeup. Thanks pin head!

inkpot · 12-23-06, 10:53 AM

Quote:

Originally Posted by sine80

cv or double carden is on the left.

Howdy! Looks just like my setup on the front of my Piggy. And it looks just like my setup on the back of my Piggy. I may not have needed the one in the rear, but I was so impressed with the CV performance in the front, that I did both ends. I can run at freeway speeds in 4x4 w/o any noise or vibration. Works nice for going up to ski country. John

Storm · 12-23-06, 11:09 AM

that was a great article, dang it. I hate it (and love it) when long held beliefs are dispelled by the experts.

tonkota · 12-23-06, 11:19 AM

Quote:

Originally Posted by inkpot

Howdy! Looks just like my setup on the front of my Piggy. And it looks just like my setup on the back of my Piggy. I may not have needed the one in the rear, but I was so impressed with the CV performance in the front, that I did both ends. I can run at freeway speeds in 4x4 w/o any noise or vibration. Works nice for going up to ski country. John

Cool. I can't run one in the back because of the off-set rear and center output NP205. I think that I may do the "Backyard Fab" by Brian from the July/August 2005 issue of Toyota Trails to make it a centered housing. Then I could run a double cardan joint.

So many choices, I can't decide. That is why this project is taking me so long. I want to build it to be the best for me and my end use.

Tankota · 12-23-06, 03:57 PM

You gonna be driving this on the road?
If yes then it will be worth it to get the alignments right and use a double cardan. I used to have a saginaw and a spicer double cardan sitting in the garage. One was rebuildable, the other wasn't supposed to be but my old driveline guy said he knew how. He also showed me how to grind down the stops on them so you'd get more angle out of the setup. Stock they don't give much angle.

When I was building my rig a few years ago I was faced with spending over $500 for a "super cool everybody wants one and you gotta get one or your'e not cool on a certain other website that I'm not all that fond of" 1350 double cardan...SCREW THAT! I only trailer the thing so I had my local driveline guy build a standard 1350 driveline for $70 and just pointed the driveline right at the t-case. I dont' drive on the pavement...ever.
I run a 350/465/205/dana60toyhybrid rear. My 38.5" swampers pretty much mask any vibrations in the rig

so if the driveline vibrates I wouldn't be able to tell anyways.

EDIT: Just remembered you have a FJ55. How long is this driveline gonna be? If it is LONG and you aren't gonna lift it much then the angles are gonna be minimal and a CV style driveline won't be necessary.