The shop that did mine just wanted the dimensions and made a brand new shaft. Said it was easier than cutting, welding, balancing and putting new u-joints in an old one. At any rate, I'm pleased with the results.
supposedly the driveshaft comes back today and we should be able to take the truck out for a test drive this evening. the only other concern i have is that the trans under load makes a lot more noise than not under load. i shifted it through the gears with the driveshaft off and it was quiet but when the shaft was hooked up it was a little noisy. nothing alarming though and it could have been because the floor pan is not finished and the trans was hitting the floor pan which could be augmenting any little vibration. is it normal for a T5 to make some noise under load?
A very small amount of gear whine isn't unheard of. Switching to synthetic ATF usually eliminates this. Make sure that the sealant used for the case is compatable with synthetic lubricants, otherwise it may start to leak...
If the noise is gone or significantly less in 4th gear, you may have an input bearing going out too though...
snarl & ernie: thanks... this sound wasn't a normal trans whine it was more of a continual, broom on concrete sound. with the driveshaft off, i ran it though the gears and it made no noise what so ever. the driveshaft is back and should be installed tomorrow.
I had the same problem with my t-5 and mine was the angle of wich the driveline was i spaced the tailshaft up and problem solved!!!
That was my initial thought, too... as soon as I saw a Ford pickup in the avatar and the thread title. But on #19, it seems that the problem is gone with removal of the driveshaft. I'd ask 'em to check. Trust me, hoping that a busy technician will remember to check what he's working on for other problems is an invitation to disappointment. DAMHIK! One other thing to check for: issues in the rear end (bent axle/wheel, etc.).. I'm guessing you haven't changed the rear axle as part of this swap, but I bring it up, just in case there was anything worked on there, or swapped. And, has anything hit the exhaust during all this work. I've run into cars that had vibrations due to exhaust rubbing on the chassis under load. And there wouldn't me much load with a driveshaft removed. Just a thought. Hopefully you'll stick the driveshaft back in, and the job will be all done. -Bill
thanks for the thoughts.... i couldn't contact the driveshaft balancing folks because i don't know who they are. besides "professionals" get all upset when you ask them a question or heaven forbid, give them a suggestion. there is no shortage of temperamental "genius" mechanics. all i can do is put my money down and roll the dice....
that's something i didn't consider. THANKS! i will probably just use normal ATF and change it often however.
he put on a new mount. the driveshaft was balanced and installed. SAME vibration problem or even slightly worse. it starts at around 30mph and gets worse the faster i go. we've ruled out the rear-end, driveshaft, u-joints, and clutch/pplate. the ONLY thing i can think of is that it's the output shaft bushing. i had this EXACT same problem with the old trans when the output bushing went bad. we even sent the driveshaft out to be balanced that time too! someone here said that there is no output busing on a NWC T5 but there has to be. HELP! i'm supposed to be in florida by now.....
There is an output bushing on a NWC T-5, check that. How is the length of the shaft? I know you said the mechanic shortened the shaft but did he shorten too much? There should only be about 1- 1 1/2 inches of slip yoke sticking out with the full weight on the suspension. If its more than that it's too much and could cause a vibration even though the driveshaft shows good balance. Pics would help.
You say you had to shorten the drive shaft Yes?. I'll bet when this happened you have changed, because the tranny is longer, the angle of the rearend to the tranny. Put some 1 degree shims in the spring and tilt the rear end up at the yolk. If it had no vibration before I'll bet that this is the problem and the shims will cure it!!
don't know, i will have to ask him. he has done a million driveshafts though and for mechanics that i know who said, "no problems", so i think he knows what he's doing. i'll look at it this evening and get some pics. we discussed this and don't think that this can be an issue because he didn't shorten it that much and it's a long driveshaft on an 8' bed. i see guys with their trucks jacked up to the sky and they have no problems. it really shouldn't matter as long as the driveshaft is in phase, should it? i'm leaning toward the output bushing. we have to check it for slop. that will probably happen tomorrow. i will print-out and give the suggestions here to my mechanic. this is so frustrating because the trans is in, the clutch is releasing and everything works. the only other thing i can think of is that the trans mount that he made is pushing up on the tailshaft. when we get it up on the lift i want to run it through the gears with the transmission jack holding up the differential to look for the vibration. i might even take off the trans mount temporarily to see if that has any effect..... we're running out of ideas.
Another thing to check for is the top of the trans hitting the floor? T-5's have the top cover with a hump for the shift rails, if this hits the floor you will get a vibration. Also look at the trans tunnel for wittiness marks of the yoke rubbing the floor.
I'm going to guess that you have a driveshaft problem just off the top of my head. But in a lot of cars and trucks that came with the T-5 stock therte were a couple of steel bars that ran from the back of the tranny up to the back of the engine. Most of the time they don't get put back when the tranny is installed in a hot rod and you hear a lot of talk of people getting vibration with these tranny swaps. Maybe those are bars are an essential pat of the tranny setup.
My bet is the driveshaft is too short now. If it is, the front slip yoke will do orbits as it is spinning because enough of it is not on the spline to keep it centered.
yeah it had those bars but he made a nice angle-iron mount for the trans so i don't think we need them. also, i've read that some folks were driving their T5 swap without a trans mount what so ever. so i don't think that this is a problem. in fact it is hitting the top of the floor but that can't cause a vibration. this vibration is associated with truck speed and gets worse after i push in the clutch. the floorboard might however transfer more of the trans noise to the interior. i was planning on dealing with that problem after i got the truck home. it might be. i'll have to check on it. that and or output bushing slop could do it. how much yoke shaft should be sticking out of the trans when the truck is sitting? does the length of the driveshaft change as the rear end goes up and down?
how much yoke shaft should be sticking out of the trans when the truck is sitting? does the length of the driveshaft change as the rear end goes up and down? It should be out about 1 1/2 in or so. Not much more. This will go in and out when the rearend goes up it pushes the driveshaft farther into the transmission. When it goes down it will pull it out of the transmission. But this is only 1/2 in or so. Jack the rear of the truck up and put it on stands. Fire the mother up. Have someone crawl under it and go for it when it starts to vibrate see what is happening!!!! If the yolk going into the trans is not wobbling around then put a jack under the pumpkin and raise the nose up about a 1/2 inch and do it again. You should be able to figure it out from there!!<!-- / message -->
I may have missed it, but I don't think driveshaft angle(s) have been mentioned...they can cause some funny things at times. Ideally, the operating angles on each end of the driveshaft should be equal to or within 1 degree of each other, have a 3 degree maximum operating angle and have at least 1/2 of a degree continuous operating angle.
that's what i suggested to the mechanic yesterday. we need to put the truck back on the lift with the trans jack under the differential, start it up and run through the gears. hopefully we will see something. if the yoke pulls out of the trans too far, that could be the problem. i can't remember the length of that yoke though so i won't know how much is sticking into the trans. i talked to snarl and he suggested removing the rear mount and seeing what happens. the only other thing that i might do is replace the tailshaft bushing.
we discussed driveshaft phasing and i talked to my mechanic about it. the shop that did the balancing should have also double checked that.
You cant put it on the lift!! It has to be on the floor with the rear tires about 3-4 in off the ground on jack stands. You want to keep the same geometry as you have now to try and locate the problem. Good Luck
Don't know if this will help, but a short, good read........ http://jniolon.clubfte.com/drivelinephasing/drivelinephasing.html
we're going to put a transmission jack under the differential to bring the driveshaft up. i don't know if we can bring it up all the way though because of the lift balance points. if that doesn't work we'll put it on the ground.
i went back out today and crawled under the truck. the first thing i noticed was a little trans fluid dripping from the front u-joint. i then grabbed the yoke and i could move it a little up and down to where it made a definite clunking sound. i think that this is the problem. the mechanic said that you need some slop in there or you will get too much friction, heating up the yoke. that's true because long ago a shop put the wrong output busing in my trans and the yoke was blue hot. so i checked my old trans and tried to wobble the the old yoke which was still attached. i couldn't get it to wiggle at all yet it was not tight to the point of causing excess friction. that confirmed my original thought that the output bushing is worn and needs to be replaced. if this turns out to be the problem, he should have caught it before installing the trans. when i previously mentioned this to him he said that it was a "snug fit". that was not my finding. so it won't be till monday before he gets a chance to AGAIN pull the trans out of the truck. i'm pretty darned sure that this is the problem. we've ruled out everything else. oh, and also because the vibration gets worse when i push in the clutch. it makes sense that when there is no load on the drive-train, the wobble is worse. but it's getting bad when a guy with a degree in fine arts has to tell a veteran mechanic what is the problem. it wouldn't be the first time though...
Why pull the trans to replace the rear bushing? They make a tool to remove it in the vehicle, looks like this. Most transmission shops have these and will even rent or let you borrow them. This slides over the output shaft, then you tighten the center bolt and it pulls the bushing out, then tap in the new one, takes less than 5 mins to do.
Good, glad you've found the problem! If you can find a tool like what shizzelbamsnapper has posted, then you shouldn't need to pull off the tailhousing. I wasn't aware they made a tool like that. I'll have to get one for myself!
hey shizz: thanks for that info. in fact the mechanic said that he should be able to remove the bearing as you suggested so he probably has such a tool. i just didn't know if that was possible on a T5. snarl: not positive if this is the problem but we've ruled out everything else AND this exact same thing happened to me at the same shop long ago with my old 3sp trans. the only other thing i want to do is replace that rear seal too as long as were going to be replacing that bearing. do the bearings come with new seals or do i have to order them seperately?
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