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1947 buick special

@Docnick - thanks, one more piece of auto info to crowd my already-limited brain…

@mountainbike Agree, that’s what they did since the torque Tube was attached to the gear box with a giant hollow ball joint inside which was the u-joint. It put a lot of stress on the engine mounts as well.

Our Roadmaster travelled well in a straight line and was very comfortable and quiet. But it did not like curves and corners. It was also, along with Caddies and Packards, a favorate gangster car with tons of room in the backseat and those long front fenders going all the way back to the rear fenders. When you see a 40s gangster movie you’ll see them often, in black, usually chauffer-driven.

Tester is still correct in regards to the driveline angle being a necessity. One of the main reasons for center carriers is to create an angle that might not otherwise be there.

Well, Tester is talking about a driveshaft with 2 U-joints. He hasn’t convinced me that he is correct. Anyway the link that he gave talked about only a 1 degree angle.
And @ok4450, the Buick had NO center carrier.

What Tester said was correct for a driveshaft with 2 universal joints, but torque tube cars didn’t have a rear joint so there was no splitting the angles like you do with 2 joints. Also, ir isn’t the u-joints that permit the change in lenght so the reat axle can move up and down, it the splines between the transmission and front yoke.
Furthermore, center carriers are not used to change angles but to prevent whip from a too long driveshaft.

I believe center carriers are also used to split angles in a long driveshaft (like on a truck). U-joints have limited usable articulation angles.

TSMB - how does adding a center carrier reduce any of the angles? If in line the angles stay the same, otherwise some increase, compared to a single long shaft.

It can break what would have been a 20 degree angle into two lesser angles. The rotating axes of the tranny tailshaft, the intermediate shaft, and the final driveshaft are not in line. Watch a few box trucks that you see on the road, where the driveshafts are visable. You’ll see many using a carrier bearing in that fashion.

But…connect two dots (transmission output and diff input with a straight line. There’s your beginning angle, equal at both. Now connect them with a bent line. One angle will increase, one will decrease. Right?

They tip the differential. The operating axis of the tranny shaft and the pinion shaft are not parallel. They intersect.

@the same mountainbe, I have noticed the carrier bearing on box trucks as you mentioned. But it seems to me that the angle of the niddle and back U-joints are worse than they would be without the center bearing. I understand that a center bearing is needed on a longer shaft.

Done correctly each angle will be less than one angle would have been. I’ve attached an International Harvester diagram that shows the concept.

http://firetrucksandequipment.tpub.com/TM-5-4210-230-14P-1/css/TM-5-4210-230-14P-1_958.htm

They also have to be phased properly such that each joint’s output wave offsets the other’s. I’ve attached a link that shows that as well.

http://www.bmwmotorcycletech.info/phasing.htm

Someone here said that the engine should tilt back in order for the oil to drain back to the oil pan. I don’t think that is true because there are 16 pushrod holes for the oil to drain down throuth and other holes as well.

@Triedaq, my dad had a cousin, who, in 1951, parked his pretty, moroon, 1937 Roadmaster in his barn and bought a new '51. Now, that was a car!! Sommething that Al Capone might have driven!!

Besides, elly, whether that would help anything would depend on where the pickup tube comes down. And if you have an engine that has the dropped area of the pan (which is where the pickup comes down) in the front and you tilted the engine backwards…well, may the engine gods have mercy on you.

Which brings up another point: pans have dropped areas for the oil to drain into anyway. Tilting the engine is, well, of no value.

Well, the OP asked if the engine was supposed to tilt down in the back. The answer is YES. All this other stuff is immaterial!!

@EllyEllis, that other stuff is so fun to talk about. Just re-read this thread.

Yeah, it has been fun. I check it several times a day.

It’s like driveshaft angles causing excessive vibration in the manure spreader…You need hip-boots for this one…