Transmission Crossmember Direction and Proper Pinion Angle

Chenn2389

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Stupid Question, I have 1994 sn95. My crossmember is labeled "TOP" and "R" and currently I have the "R" on the passenger side because I assumed you would install it with the "R" on the passenger side while looking towards the flywheel during assembly. Is this correct?

Also, chasing some vibrations.

I adjusted my double adjustable control arms to Parallel -2*.
I have poly bushings everywhere so under acceleration the pinion should rotate around 2 degrees up bringing the engine/trans and pinion parallel.

Here are my angles. These were taken with the front of the car on jack stands on the frame and the axle on jack stands in the rear to load the suspension.

Before:
Trans/Crank: 3.8* down towards the rear.
Drive Shaft: 5.7* down towards the rear.
Pinion: 0.7* down towards the front.

Operating Angle FWD: 1.9*
Operating Angle AFT: 6.4*

After:
Trans/Crank: 3.8* down towards the rear.
Drive Shaft: 5.1* down towards the rear.
Pinion: 1.8* up towards the front.

Operating Angle FWD: 1.3*
Operating Angle AFT: 3.3*
 

spittinfire

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I've never run parallel U joints. I would run the pinion at 2-3* down to match the trans.
 

lwarrior1016

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If the trans points down, the diff needs to point up the same amount. Equal and opposite angles.
 

Chenn2389

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If the trans points down, the diff needs to point up the same amount. Equal and opposite angles.

I have seen this video. I also followed method 2 from here https://www.baselinesuspensions.com/info/pinionangle.htm. Which suggested a pinion angles of -2.5 to -3 for cars with all poly bushings, but it doesn't state if the driveshaft "U" shape (trans down to the rear, pinion down to the front) or "Z" shape (trans down to the rear, pinion up to the front). I set my pinion -2* relative to the crank in the "Z" shape car does not like this at speed. The directions for my control arms also stated -2 to -3 pinion angle.
 

Notthenow

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Iwarrior is correct, pinion up same amount trans output is down. In steady state they will be that way and ujoints will work best. Normal suspension movement will keep them within tolerable angles. Extreme set ups are usually for drag racing.
 

Chenn2389

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I set the pinion up the same amount the transmission is down. I put in a new T5z transmission the same time I set the pinion angle and am getting vibrations still. But I noticed the vibrations are consistent with engine RPM. It feels like the input shaft is wobbling in the pilot bearing. Then I combed through some pictures and noticed my pilot bearing is pushed in way too deep into the crank. like the bushing is noticeably too thin. I will be pull the transmission this weekend to swap the pilot bearing. I looked on the input shaft of my stock T5 and could notice that the wear grooves were less than halfway up the surface where the pilot bearing should be.
 

lwarrior1016

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One other thing, do you have the alignment dowels on the flywheel for the pressure plate? And do you still have the dowels in the engine block that the trans bell housing aligns on?
 

Chenn2389

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If the trans points down, the diff needs to point up the same amount. Equal and opposite angles.
Yes the dowels are in the flywheel and the bell housing. Here is the picture of the pilot bearing look how it’s noticeably too thin and isn’t sitting flush with the crank. I took this photo back in May/June due to rear main seal leak. My vibration issues started immediately after installing the transmission after this photo. I believe it may be because I put the transmission in by hand without a jack and didn’t get the input shaft into the pilot bearing properly.

This first photo is my pilot bearing the second photo is the better ford racing roller type pilot bearing. A huge difference.BA2AB83C-71E6-4A03-8E3C-D56ACA5CC13E.jpeg365E36D4-AA9D-4629-94C5-B90597E7C7F1.png
 

Notthenow

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Your bushing looks too deep. They are normally flush with the crank flange face. Bronze isn't bad unless it is worn, as it was the standard for years.
 

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