T5 input shaft preload...thoughts?

86turbo

Member
Apr 8, 2006
183
0
17
If an input shaft wasn't preloaded enough what symptoms would it cause? I seem to have this slight grinding noise coming from the bellhouisng area when the car idles too low.. it almost sounds like stuff is shaking around. Funny thing is, my friends car with a t5 makes the same sound when the rpm drops below 500. Another symptom I have is a rpm dependent vibration (approx 2500 and up) and I have ruled out TOB, clutch, flywheel, ignition, input shaft pilot bearing, etc. Car runs fine and last time trans was out of the car I noticed the input shaft has side to side play more than I would imagine is allowable. Could this cause rpm based vibration???

thanks,

Drew
 
You need to get a new throwout bearing retainer. Go to astroperformance.com I had the some problem with mine before the input shaft had alot of play before i install a new retainer and shim to tighten up the preload.The retainer comes with a new seal and shim and it will help with you tighten up the preload plus stop the noise that you are hearing. GOOD LUCK.
 
Side to side play is normal. It's in and out endplay that you are trying to eliminate. A quick check is to grab both input and output shaft and simultaneously pull and push them in and out. They shouldn't move.

I don't have the specs on shimming the input shaft in front of me right this sec, but it's very small. You are going for 0.000 endplay basically but with error on the side of slight preload. Too much preload will put unnecessary pressure and wear on the input bearing, but you def don't want in and out movement at all. Some guys intentionally set preload a little tighter with the thinking it will help support the mainshaft and keep it from flexing. No idea how true this is though
 
BTW, the last t-5 i tore apart that had a sort of grinding noise to it when just idling had this when i pulled the input shaft out


attachment.php
 

Attachments

  • DSC00034.webp
    DSC00034.webp
    85.9 KB · Views: 4,986
I did't say it was just the bearing retainer it's the shims that's behind the retainer. You may want to try shimming it with a thicker shim and it should be little to no play on the input shaft and when you turn it by hand it should turn with a slight drag be still be easy to turn and there should be no side to side play with the right shim. The reason why i said the retainer is because i did't know if you replaced your's and a few years ago i had the same problem and i replaced the retainer and used a thicker shim and it worked. So it's not the retainer it's the shims and you may need a thicker shim to get the right preload and no side to side movement.
 
I disagree, but i'm not there to see what it's doing in person so it's really tough to diagnose

But a 2500+ RPM vibration would have me suspecting anything from input shaft forward. I just don't think lack of preload would cause vibration. It would cause post #5.
 
a lot of advice being passed around here by people who shouldn't be giving advice...For those of you have have never rebuilt a t5 or set endplay before, please don't give advice. You can't give accurate advice on something you've never done before.(mustang 5l5...you know your stuff about t5's, not talking about you)

I preload all of my input shafts with .002 thousands...just a hair. I don't go higher than that if I can help it, but usually never lower.

As well, "preload" isn't necessary. As 5l5 said, you're shooting for .0000..or NO play, no preload. The reason for preload is that typically with a rebuild, the new bearings still have to seat in. If you don't preload slightly, then as your new bearings seat in, you're going to wind up with play. Preloading slightly will give the trans some room to get closer to .0000 as the bearings settle in.

You're not going to hear a grinding noise from having play in your input. (this is assuming you have just slight average play. If you have a LOT of play, then anything goes) 5l5, that's a bad looking 4th gear. what do you think caused that?? The worst that I've seen from having too much play in the input is popping out of 2nd gear. It will cause accelerated wear of course, but it's not going to have constant low rpm noise.

In fact, from my understanding, it's quite common for t5's to make a little noise at idle. My theory behind this is the most likely...If you spin the cluster shaft (case has to be apart and mainshaft has to be out..it makes this choppy sound from spinning on the bearings. First time I heard this, I pulled it out 4 different times and swapped out bearings, before I realized that every t5 under my bench made this noise. This noise you hear could be ok, and not a reason to be alarmed. You'll have to use your better judgement to determine whether that noise sounds like parts are meshing wrong or not. I'd hate to see you rip apart a t5 for no reason.
 
thanks for the info......I checked with yet another friend of mine who has a t5 fox and his makes than noise when the engine idles too low. Kinda like stuff is rattling around, i dont know. Good info though
 
Go to astroperformance and talk to a pro about the problems you are having. As i said before when i was having the same problem that's who i talked to and what they told me worked. But what worked for me may not work for you so that's why i recommend you talk to them. But for some reason just because someone rebuilds a T5 doesn't means he knows what he's talking about. I don't know why this guy is thinking i don't know what i'm talking about because if you know so much about t5's then you would know that as they get old there will be some play in the input shaft and the only way to fix the play and preload is to shim it or rebuild the T5. I was just trying to help the guy troubleshoot his problem not trying to prove that i know everything.And also you shouldn't assume i don't know what i'm talking about because i have worked on T5's before too. plus you don't know yourself what the problem maybe you just assume you know what the problem is just like i assume i know but we are not there to hear how it sounds so we both can assume. But try to stop putting people down for trying to help someone and remember just because you rebuild T5 does not mean you know what this guy's problem is. Because i joined this forum to help people not to prove how much i know and not to put people down if they could be wrong. Who knows you maybe wrong but you gave good info and tryed to help this guy and that's what it's all about helping people.
 
5l5, that's a bad looking 4th gear. what do you think caused that??


No idea really. The entire trans was junk. Input shaft junk, countergear junk, 2nd and 3rd dog teeth were mashed to hell and you don't even want to know how much metal i found at the bottom stuck to the magnet. Mainshaft was scored where the input shaft roller bearings ride, so that was junk too. Basically the only usable parts are the case, 5th gear, and the shift linkage/forks and misc small parts. I got them all bagged and boxed up squirreled away

I was thinking of making a Z-spec T-5 out of it, and machining down the mainshaft so i can run the 1993 Cobra roller bearing style input shaft.

Friend of mine's step-sister bought a Fox GT. She's 16 and fell in love with it. Unfortunately the shiny red paint hid the fact that the car needed some mechanical work. So basically I traded her a 53K original mile T5 in great shape in exchange for the ratty one...and helped install it. I'm just a nice guy. :)
 
Because i joined this forum to help people not to prove how much i know and not to put people down if they could be wrong. Who knows you maybe wrong but you gave good info and tryed to help this guy and that's what it's all about helping people.

Don't worry man. Your help is appreciated. Welcome to the boards
 
hanlon used to sell a kit to machine the shaft down. The problem is that the cobra mainshaft has a groove for an extra clip that I believe holds down the 3/4 slider that the normal shaft doesn't have. I know for sure though that there is an extra clip there, so what hanlon did is sell a cup that goes under the bearing which presses down on the 3/4 assembly and keeps it from moving. I know on the reg shafts, that slider is pressed on, but I believe (again it's been a while) that the 3/4 slider on the cobra/z shaft just goes on and is held on by the extra c clip, then the tapered bearing gets pressed on after that. I've got one of those trannies under my bench. I'm not sure that he sells this cup piece any longer though, and simple machining won't work unless you find a way to make up for the lack of groove for that extra clip.

I know the shop i get parts from actually has a used z/cobra shaft that they'd sell me for $75...pretty good price. Perhaps I should pick that up.

In the end though, that little cobra pocket bearing isn't a make it or break it deal. It adds I think 10-15 pounds extra torque and allows for more preload on the input for assembly, but that's about it.

I've built 4 z spec super alloy trannies from normal wc trannies so far using the standard needle type insert bearings in the input, and so far so good.

Additionally, there is some interesting info regarding the z spec kits. (I got bob hanlon on the phone the other day and chatted with him for about 20 minutes on this)....with just about every "kit" offered on the net, they're all the same (including the shop that sells me these things locally)...the z kit that's offered gives you a tremec 1,2 gear, but a made in india 3rd gear, 4th/input and india cluster. THis is just a big problem according to bob. He says if you're building a z that you really want to last, you can't run that india crap that everyone is pushing. He said that the problem is that everyone wants something for nothing, and as a result everyone sells the cheap stuff.

I have used the india kit 4 times now without issues, but I do know MFE on the corral busted a made in india z spec third gear. He's replaced it and so far, so good.

If you call up hanlonmotorsports, they can sell you the z super alloy kit for about $350. The gear box sells this same kit for about the same price.

Hanlon told me he can sell the "real" kit with 100% tremec parts, but didn't have a price off the top of his head. Next time I put one of these together, I'll have to get a quote on the real stuff.


JKA, no offense intended..that's why I didn't include any names. Nothing was directed towards anyone specific.

As for myself, it's just a side thing I do with t5's, but I've got about 20 under my belt, and imo that darn near qualifies me as a t5 pro.
 
hanlon used to sell a kit to machine the shaft down. The problem is that the cobra mainshaft has a groove for an extra clip that I believe holds down the 3/4 slider that the normal shaft doesn't have. I know for sure though that there is an extra clip there, so what hanlon did is sell a cup that goes under the bearing which presses down on the 3/4 assembly and keeps it from moving. I know on the reg shafts, that slider is pressed on, but I believe (again it's been a while) that the 3/4 slider on the cobra/z shaft just goes on and is held on by the extra c clip, then the tapered bearing gets pressed on after that. I've got one of those trannies under my bench. I'm not sure that he sells this cup piece any longer though, and simple machining won't work unless you find a way to make up for the lack of groove for that extra clip.

I know the shop i get parts from actually has a used z/cobra shaft that they'd sell me for $75...pretty good price. Perhaps I should pick that up.

In the end though, that little cobra pocket bearing isn't a make it or break it deal. It adds I think 10-15 pounds extra torque and allows for more preload on the input for assembly, but that's about it.

I've built 4 z spec super alloy trannies from normal wc trannies so far using the standard needle type insert bearings in the input, and so far so good.

Additionally, there is some interesting info regarding the z spec kits. (I got bob hanlon on the phone the other day and chatted with him for about 20 minutes on this)....with just about every "kit" offered on the net, they're all the same (including the shop that sells me these things locally)...the z kit that's offered gives you a tremec 1,2 gear, but a made in india 3rd gear, 4th/input and india cluster. THis is just a big problem according to bob. He says if you're building a z that you really want to last, you can't run that india crap that everyone is pushing. He said that the problem is that everyone wants something for nothing, and as a result everyone sells the cheap stuff.

I have used the india kit 4 times now without issues, but I do know MFE on the corral busted a made in india z spec third gear. He's replaced it and so far, so good.

If you call up hanlonmotorsports, they can sell you the z super alloy kit for about $350. The gear box sells this same kit for about the same price.

Hanlon told me he can sell the "real" kit with 100% tremec parts, but didn't have a price off the top of his head. Next time I put one of these together, I'll have to get a quote on the real stuff.


JKA, no offense intended..that's why I didn't include any names. Nothing was directed towards anyone specific.

As for myself, it's just a side thing I do with t5's, but I've got about 20 under my belt, and imo that darn near qualifies me as a t5 pro.
 
Well you may think your're a pro and you may have 20 under your belt but your info maybe wrong too. I know you did not say any names but put two and two together there was only a few quotes before you jumped in making a stupid comment about the guy getting the wrong info from somebody that' never rebuilt a T5. You do not know what i have done and you do not know me. I am a certified tech/part time engine builder and have worked on C4 trannys T5 trannys and AOD trannys. But i recommend the guy check with astro because they are good guys who really know there stuff about T5s.I just work on them from time to time and half of the stuff i do deals with engines and not trannys. It' good you tryed to help the guy too but how does that sound to try to belittle another man because you think it's the wrong info when you do not even know that person. Keep on helping people but keep your comments to yourself.Because you don't even know if you are quoteing the guy the right info just because you have fixed T5s before this guy may have something else wrong. So that's just crazy to try to belittle someone for trying to help a guy that needed help.:Zip2::Zip2::Zip2:
 
Jesus christ already, I knew it was the wrong info because I build ****ing t5's you moron.

I was simply making a point that some people were about ready to have this dude ripping apart his t5 when there is likely/possibly nothing wrong with it. Bad advice was being given by people who have never torn apart a t5 or troubleshooted it on that level.

I've spent the better part of the past ten years on message boards passing on only what I've learned through first hand experience. Rather than be insulted, learn from it. Go pass on your engine building experience....That's some good stuff to know...save the t5 info for those who know them.
 
  • Like
Reactions: NurseGuy
damn guys, chill out. The guts in the t5 are from astro, it's their alloy kit. Idk, maybe the mainshaft is slightly bent or something. It's not that bad anyway, goddamn this site will never change. I appreciate everyones help btw