pufferfish
Supporting Vendor
So, I finally got all the necessary tools to dissect my original transmission that ground 4th gear. I got it apart over the weekend and what I found was a very sophisticated piece of mechanical meshing inside. I don't see a cheap piece of chinese junk at all. The gears are all broad faced with excellent surface machining. The bearings are good sized and the fits are tight. That's the good...now here's the bad.
The synchro teeth are tiny by comparison to even the old T-5. There is more of them, which is a good thing, but being so small, they are subject to no being very tolerant of less than perfect shifting. I had some issues learning how to shift 1-2 in the early days of ownership and since then, i get the "nibble" on occasion. well, i found out the 2nd gear synchro teeth faces were broken off on about 1/3 of the teeth. so, its my fault they got that way, but the T-5 would have been much more forgiving. I wouldn't necessarily call it a ford mis-step though. lots of teeth make for a transmission that can actually shift at 8000rpm. you can't ask a t-5 to do that. it simply will not. My 4th gear synchro was, much to my surprise, perfect...which leads me to the next issue.
I am sure you have all heard about plastic shift fork pads and its true. You have also heard they are weak and that is also true. one of my 3-4 shift fork pads was broken. That is what caused my 4th gear engagement issues. liberty gear sells brass pads for $25 each. this is a must if you ever have your case torn apart! You actually can't even buy just the pads from ford (they come with the forks), so its nearly cost neutral.
Lastly, the shift rail stop. WTF were they thinking? you have a round shaft with a deep notch cut into it about 1" wide. Then a hardened steel pin with a step down at the end. on that stepped end is a piece of plastic. the plastic hits up against either side of the notch...a hardened steel flat banging against a round plastic part. the issue of plastic is of course first, but after that, who puts an impact force on a point load, such as banging a flat part against a round one? the pin should have flat faces to distribute the load! mine was obviously crushed. it went from a 12mm diameter to an oval shape that is 10.5mm wide. so, my shift forks were over-extending by 0.75mm in each direction. maybe thats not a ton, but its enough to put a huge strain on the shift fork pads! revolution auto sells a reworked pin that has a brass piece on the end in place of the plastic. its kind of expensive (don't recall the price off hand), but is worth it. its a part that comes out without taking the case apart. i wonder if its accessable?
So, to conclude, its got "good bones". it should be able to reliably transmit way more power than ford advertises. but ford cheaped out on the little things that will grind these things to a halt. To prevent issues on your OE trans, rowing the gears accurately is essential.
and, no, i didn't take any pictures. i wish i had. i will try to do that when i rebuild trans #2...5th gear is the issue here. wanna bet its shift fork pads again?
The synchro teeth are tiny by comparison to even the old T-5. There is more of them, which is a good thing, but being so small, they are subject to no being very tolerant of less than perfect shifting. I had some issues learning how to shift 1-2 in the early days of ownership and since then, i get the "nibble" on occasion. well, i found out the 2nd gear synchro teeth faces were broken off on about 1/3 of the teeth. so, its my fault they got that way, but the T-5 would have been much more forgiving. I wouldn't necessarily call it a ford mis-step though. lots of teeth make for a transmission that can actually shift at 8000rpm. you can't ask a t-5 to do that. it simply will not. My 4th gear synchro was, much to my surprise, perfect...which leads me to the next issue.
I am sure you have all heard about plastic shift fork pads and its true. You have also heard they are weak and that is also true. one of my 3-4 shift fork pads was broken. That is what caused my 4th gear engagement issues. liberty gear sells brass pads for $25 each. this is a must if you ever have your case torn apart! You actually can't even buy just the pads from ford (they come with the forks), so its nearly cost neutral.
Lastly, the shift rail stop. WTF were they thinking? you have a round shaft with a deep notch cut into it about 1" wide. Then a hardened steel pin with a step down at the end. on that stepped end is a piece of plastic. the plastic hits up against either side of the notch...a hardened steel flat banging against a round plastic part. the issue of plastic is of course first, but after that, who puts an impact force on a point load, such as banging a flat part against a round one? the pin should have flat faces to distribute the load! mine was obviously crushed. it went from a 12mm diameter to an oval shape that is 10.5mm wide. so, my shift forks were over-extending by 0.75mm in each direction. maybe thats not a ton, but its enough to put a huge strain on the shift fork pads! revolution auto sells a reworked pin that has a brass piece on the end in place of the plastic. its kind of expensive (don't recall the price off hand), but is worth it. its a part that comes out without taking the case apart. i wonder if its accessable?
So, to conclude, its got "good bones". it should be able to reliably transmit way more power than ford advertises. but ford cheaped out on the little things that will grind these things to a halt. To prevent issues on your OE trans, rowing the gears accurately is essential.
and, no, i didn't take any pictures. i wish i had. i will try to do that when i rebuild trans #2...5th gear is the issue here. wanna bet its shift fork pads again?