Hi guys,

Working with an '01 S80 that I've had since it had 400 miles on it (12 years? holy crap!). I'm going to guess that it has ~60k on it now. It spent the most of its years in my race car, so life has not been easy even though I'm pretty light on transmissions.

Last year I scavenged it from my coupe to throw in my sedan with a b20. Of course, the only seal I didn't replace in the whole project, the input shaft seal, is weeping a little. So I'm going to be pulling it out soon to fix that.

There are a couple of issues I'd like to address while I'm in there.

- There is a slight noise while the clutch is out and car in neutral, i.e. sitting at a traffic light. Input shaft bearing maybe?

- Slight scratch going in to third at high rpm. Not banging the gears, just normal, smooth-ish shifting.

- The car has a vibration between 20-30mph. I'm confident that it's associated with the output side of things since it's in the same speed range whether I'm in 2nd or 3rd gear. So far I've replaced both axles, and I have a new bearing for the intermediate shaft sitting on the workbench for when I have time. I feel like it might be the diff bearings though. Vibration was not there before the swap.

- I'm thinking about doing the LS fifth gear while I'm in there. Aside from the gears, is there anything else I should be watching out for?

Basically I need to try and have everything ready to go when I crack it open, since I'll be doing it in one day or so. I've done a few transmissions in the past, I've just never really had to diagnose little things like this... mostly obvious stuff like broken gears or trashed synchros.

What all should I plan on having to replace? Help is appreciated.

 

It sounds like you have a good idea of what is needed. The ISB is probably what is causing the noise at idle but you may want to go ahead and replace the rest of the shaft bearings while you are there. The grind in third is common and can usually be fixed with a 3-4 sleeve set. The vibration is probably not from the trans, check the diff bearings when you have it apart but they usually do not go bad at this mileage and should not cause a vibration at a certain MPH. Tires, CV joints, support bearing are more likely. The LS 5th is a straight swap, just make sure you change both 5th gears as a match set.

Good luck with the build.

 

I dont know if this helps at all but i had a slight vibration above 80mph and i assumed it was always the axles until i decided to do all the bushings on the front end and noticed the vibration was gone.. Hope it helps.. Good luck

 

Thanks guys. As far as rubber parts go, the lower torque mounts are definitely on my to-do list before I get to the trans. I really don't think the vibration is suspension bushing related, and the fact that it comes through the floor but not through the wheel leads me to believe that it's inboard... somewhere between the inner joints and the trans. I forgot to mention that a tire rotation also did not fix it, so tires are out of the equation.

It seems, for what the individual parts cost, that I'll probably be better off dealing with it for a little while and then pick up a whole master rebuild set when I can.

 

Yea its hard to diagnose something without being there.. But i changed axles twice and two sets of tires and always threw it on the alignment rack every 3 months.. 2 years later i replace all bushings on the front re align it and bam whole new car amazed me.. Just keep an eye out when pulling the tranny..

 

I would get to it sooner rather than later. If you wait you will have a higher chance of needing to replace some parts that are still good right now.

If you're not having 1/2/5/R shifting issues, the Master rebuild kit could just be throwing money away (unless the parts are worn but the problem hasn't presented yet).

 

Very true.

 

My input shaft bearing seal has been weeping since last fall, but just last week, I started hearing what I think is the ISB failing. Kind of a mild grinding with a rythmic "tick-tick" once per second at idle. Is that how yours sounds spAdam?

Re: intermediate shaft bearing - I bought a new one with some new axles a couple of years ago. I took it to a machine shop I trust to have the old one pressed out and new one pressed in, but he damaged the rubber isolator and shaft mount was ruined. His impression was that it was not replaceable.

I've had bad luck with axles. After having 3 or 4 different sets in the same car with the same motor, I can tell you that it is the primary source of these speed specified vibration problems. I repacked the inner CV's on my current DSS Stage 1 axles with Redline CV about a year ago and they were great, but after 30K miles or so, that wobble around 40mph is slowly coming back. I'm thinking about springing for some Raxles, but yungmulacrx's point about bushings is a good one too. This shell has 170K on and all the bushing are original.

 

I don't get the ticking, but when the car is good and warm (stuck in traffic) I can definitely hear a grinding noise with my foot off the clutch (Input shaft spinning). It goes away when I depress the clutch (Input shaft idle). I've found a couple of seal/bearing kits, they seem to be more reasonable than piecing together only the parts that I need and will cover the diff bearings too. I need to see what kind of H-T discounts are available.

I ended up going for Raxles as well, after getting frustrated with even the better of the parts store variety. They really are getting worse by the day, I used to use them constantly with no problems. You know the market is saturated with **** when the new chinese axles are cheaper than domestically remanufactured ones. I couldn't be happier with the Raxles product. I used to use them on customer cars (when I could talk them into it) a ton when I had my shop, this is the first time I've used them on my own though.

The axles changed nothing about the characteristics of the vibration though. At least I can eliminate that variable from the equation, the old ones were in questionable condition anyway.

I need to do that intermediate shaft pronto. Then one more variable down. I won't have any spare time for the next 45 days or so though. Two jobs + last semester of school ever + FSAE deadlines + Senior Design + continuing jobhunt = too much poop/not enough butthole situation.

I really hate throwing parts at a car and hoping for results, but I am at least doing it with some semblance of order, and replacing things that need to be replaced on a 12 year old drivetrain anyways. It's not the most scientific method, but short of mounting accelerometers all over the place and doing modal analysis to track down the location of the vibrations, it's all I've got.

 

I found a "master" rebuild kit for $650. That's more than I can justify throwing at THIS tranny though, so I'm going to have to tear it down and order only what I need.

The bearing is making more noise today than it was on Monday. This is how it sounded then:


This is my daily and good for a few hundred miles per week for work. I guess I'm wondering is I need to get another tranny in there now before the failure is catastrophic.

 

Pm synchrotech if you need a rebuild kit they'll take care of you.. Or find another tranny but that is always a gamble.. Even if you ordered all honda oem parts i dont think it would add up to 650..

 

Sounds like an input shaft bearing to me. If you are not having shift issues, you will probably not need the master kit with synchros and sleeves. Let me know what you find after opening the trans but do it soon as it will not last much longer.

 

I definitely will, thank guys!

Sorry to thread-jack spAdam. I'll come back and update when I get this thing cracked open.

 

No worries. Sounds like we have similar issues, no sense in cluttering the forum with a duplicate thread.

 

spAdam,

I picked up a cheap tranny with no reverse this weekend. Popped it open yesterday and found it also has an input shaft bearing gone bad.

I found this on the magnet:



Here's how the ISB looked when I pulled the mainshaft out:



The ticking noise in mine must be the bearings hitting eachother without the cage in place.

I found the oil passage on the mainshaft blocked by an old piece of dried Hondabond. Someone was not careful to clean all the debris out of the case last time it was open. Probably caused oil starvation to the ISB.




If you're ONLY going to replace the ISB, I'd say you could bang it out in about 2-3 hours, excluding time to remove and install the tranny of course.

I'm hoping to get parts this week and reassemble next weekend. I'll let you know how it goes.

 

I always put the tranny case in the parts washer and half of the time the bearings will just fall right out cause of the hot water.. If i was you i would also take out the cs and make sure all those holes are good and clean..

 

Hey Spadam,

I just tore into my trans because of the same 3rd gear symptom. Just a little banged up..lol








good luck with your rebuild. I just ordered the 3-4 sleeve set.

 

Ouch!

Thanks man, I have to find new work before I dump any money into the car though. I think I'm going to end up doing a 3-4 synchro/sleeve, seal and bearing kit, and the ls fifth. Should cover all of my bases plus a couple extra bearings.

 

Finally getting close to pulling the trigger on this. Maybe toward the end of the summer when I can take an extra day off of work to guarantee myself a full weekend to get it done, in case I run into any speed bumps. I know I can pull a trans, rebuild it, and get it back in in a day, but I don't like to rush anymore.

Looking at my options, it's actually a little cheaper for me to buy a whole seal/bearing/syncro kit and add the 3-4 sleeve than it is to just buy the seal/bearing kit and add the individual syncro/sleeve. So I think I'm going that route.

Still debating on the ls fifth gear though.

 

I wouldn't do the LS 5th.

 

I'm on the fence about it. I have a 60 mile round trip commute every day, dropping 300 rpm at 70mph would be just about right for this motor. The flipside is that the gsr fifth gear is totally usable around town. I'm still running the p75 ls intake manifold (for now), so I have a torque peak around 2700-3000 rpm that makes it totally tolerable to keep the revs down.

 

Using the LS 5th will likely drop your fuel economy. You'll also need to wind 4th out more before shifting.

 

Fair enough. I need to take a look at some logs and do some calcs to see what effects it would actually have on mileage.

What are your opinions on carbon syncros? Worth the extra $50? Longevity? I see some people saying that they have 20k or whatever with no problems, but that's about a year for me.

 

They do work better than brass synchros and last longer on high power, high RPM setups (700whp/9k+). As far as street longevity they should last longer but I don't have any customers with a ton of miles on them yet. Once I see a set with 100k+ on them and can measure the wear then I'll be satisfied if they're wearing less than stock.

 

I have had a handful of the earlier version synchros fail in customers trans. The bonding between the brass and lining has apparently been corrected among other things. I have not seen any failures of the latest revision yet. If you choose to get the carbon ones go direct to sychrotech, not another retailer that may have older stock.