J B

I bent a top shaft part #9601 in a ft b4.I went out and got a new one,put it in and put the gearbox back together.i free spun it with my hand and it sounds like a rock is in my gearbox and is slitly binding.i take it back apart and inspect the top shaft first and to my saprize its made vary diffrent.First thing i noticed was the gear part of it is coted black,the shaft on the end of the gear part(the part that rides on the bearings) is a hair longer and the teeth are slitly smaller witch is probably the main cause of the rocky sound.so i figure it might be my idler gear and/or my diff gear is worn.i go to my lhs and get them and still the same noises.my only conclusion now is they are making the gearbox gears diffrent because of the new 4.1's and im geting 1 or more of the wrong version of gears witch isnt letting the teeth mesh correctly.

Any help would be greatly appreciated thanks.

BuggyKing

iTrader: (17)

You could have damage to the idler or diff gear. Also make sure all your bearings in the trans are free and not binding. Another thing when you put the trans back together that you don't overtighten the trans screws as to this will bind the trans up.

J B

I replaced the idler and diff gear as i mentiond in my previous post,all bearings are free,i dont even have to tighten the gearbox and it makes this noise,and last night i tryed puting the old top shaft back in and it sounds smooth as butter.i have decided to look for the older version of the top shaft that came with my car(the one thats bare metal not coated in black)

if anyone knows where i can find one let me know thanks.

BuggyKing

iTrader: (17)

That is interesting maybe the top shaft tollerances from AE are off.

1Fastpede

iTrader: (53)

My FT-B4.1 transmission was loud and dirty sounding right out of the box! i did everything to fix it and the only thing that worked was to swap all my gears from my spare diff. everything worked fine it was just loud!

ifuonlyknew

iTrader: (7)

Let me see if I understand you, because your posts spelling and punctuation made it very difficult to read. First thing is you are supposed to put a space after a period or a comma. I read ft b4.I as ft b4.1. This is important because I thought you have a b4.1 and were trying to replace the b4.1 topshaft with a b4.1 topshaft. This may be your problem. I think AE did a running change with the transmission case and topshaft. It has been 5 years since I ran a B4, but I know the topshaft used to be made out of solid aluminum, but since they started making all of their parts in China they switched to a cheaper setup that has an aluminum shaft and a steel gear. I think they also changed the transmission case. With the old case you litterally had to have the screws finger tight to make the transmission spin freely. You had to use locktite to hold the screws in. I think they re worked the mold of the transmission cases so that you could actually tighten the screws and not have it bind up. When they did this they may have found it necesarry to change the specs of the topshaft. This is why your new topshaft is a little longer. I imagine this is also when they decided to make the gear out of steel to save money. The grinding noise is probably because the topshaft gear is rubbing on the transmission case. So you have two options, buy some new transmission cases, or you can try and scour the internet to find an old topshaft. This next thing is in bold so you will pay attention to it and hopefully learn something. NEXT TIME YOU BUY A PART TO REPLACE SOMETHING THAT IS BROKEN OR WORN OUT, COMPAIR THE TWO PARTS TO MAKE SURE THEY ARE THE SAME. DON'T JUST ASSUME THAT BECAUSE THEY HAVE THE SAME PART NUMBER, THAT THEY ARE THE SAME! The gear being a different color is something that is pretty obvious, you should have noticed that right away. My suggestion is when you get the new transmission cases, that you compair them side by side and see the difference.

brickshouse

iTrader: (7)

+1 on punt. and spelling.....i had an original b4 from 2004 or 2005 and it had steel topshaft...not aluminum. The replacement ones are black, I replaced mine with no problems...may be a faulty part, have you tried a different topshaft? They make thousands at a time, one of the kids in the sweatshop prolly missed.

stu22

How did you bend the top shaft?

I suspect you broke something else. The thing is isolated by the diff and the counter gear on one side, and the spur/slipper and pinion on the other, so bending it would take some work.

GizmoJunkie

iTrader: (5)

It is hard for me to imagine bending that as well...

Can you see a strange runout in it? Or do your slipper plates not seem to runout well any more? At one time i had managed to get grit in behind the inside plate that made the spur wobble, just a thought, might save you some more hassle.

Also as mentioned i would check the bearings, i would assume the bearings would fall apart before bending up a top shaft.