Side To Side Driveline Angle (1 Viewer)

[warpdriv]

Hi Everyone,

I'm doing an conversion project where I'm putting an FJ60 case in an FJ80. From the looks of things, I will need to locate the tcase to where it is not a straight line from tcase flange to rear diff flange on a horizontal plane (side to side). I plan on driving this on the street.

I've being google'n for drive shaft angle specs, and it looks like I can have 5 degrees max at highway speeds.

I know this is not hardcore, but I'm posting here because most of the folks who do fab work, hang out here. What do y'all think?

Thank you for your help.

 

[Mace]

it'll be fine

Old cruisers had a centered output and offset rear axle.

 

[GarageRat]

What Mace said. Driveshaft doesn't care how it's angled so much as the total angle being put on it.

 

[BellyDoc]

Just pay attention to the total angle that you get between transfer case output and driveshaft at extreme suspension droop, and at the driveshaft - pinion angle. U joint angles are responsible for two potential concerns. One is increased stress. The other is wobble.

The formula for compound angle is a little tricky to derive but you can look it up if you want to. I suggest not even calculating. Just get a read off of the joint using a sliding T bevel and some straight edges. Rotate the tool around till you find the tightest angle and call that the number.

The fraction of torque that converts to driveshaft stress relates to the cosine of the angle. (If you're measuring off the inside of the angle between two sections of shaft, then subtract this number from 180 to get the angle representing "degrees of deviation from perfectly straight")

If the transfer case to driveline angle and the driveline to pinion angle are equal and opposite, then the driveline shudder created at one end is cancelled at the other (at the cost of increased stress/strain and loss of torque).

That assumes that the joints are in phase. It gets completely weird if you take apart a slip joint and put it back where the yokes are at different angles.

 

[shelfboy1]

many military vehicles had and have offset d shafts my 6x6 has one in the rear thats offset and its 68 years old with no problems .

 

[warpdriv]

Cool. Thank you for the responses.