Clutch grinds when downshifting

[drethib]

I have a 90 talon awd I shift from 3 down to 2nd and it'll give out a grind before it slips in. It's shifts slightly easier in lower rpm. Any advice in what the cause is? I want to know if my clutch needs to be replaced unless it's a minor fix that I am overlooking. Any feed back would be great.

 

[cheap90gsx]

When was the last time the transmission oil was changed? I would look into getting good oil in there.

 

[drethib]

I have royal purple in my transmission. I did top it off with some other brand transmission oil. Does it make a difference if there are amounts of other fluid added? What's the recommended amount for filling?

 

[cheap90gsx]

I would suggest NOT using royal purple full synthetic in your transmission you are suppose to be using the redline oils or something. I say that because I've tried using full synthetic and i completely blew out 2nd gears syncro. V- what he said.

 

[nyTalonTsi]

Pennzoil syncromesh.

 

[Defiant]

Any advice in what the cause is?

Yeah. It's all those people telling you that double-clutching is pointless with a synchro gearbox. Just like they told all the previous owners. Now you're the one who gets to rebuild it.

 

[My1GLaser]

Use Redline MT-90. Its a synthetic GL-4 manual trans fluid for use with yellow metal synchronized trannies.

I use 1.25qt MT-90, 1qt MTL, and .5 qt lightweight shockproof.

Try adjusting the clutch pedal assembly. I am sure a search will pull something up on tuners.

Clutch Adjustment

 

[sonik619]

Don't you have to match the rpm when down shifting?

 

[5150DSM]

Most likely not the clutch, though I would drain the tranny and fill it with Penzoil Syncromesh or GM Syncromesh(for twice the cost of Penzoil) See if that helps. More likely, is that your 2nd gear synchro is on its way out and the fluid change will only be a band-aid. I drove for over a year with a grinding 2nd synchro but in the end the tranny ate shit and had to be rebuilt. Good luck.

 

[loba]

A 1g DSM with a 2nd gear grind? UNPOSSIBLE!!

In all seriousness though, it's most likely you're syncros. Every stock 1g in the world will eventually have problems with those damn 2nd gear syncros. Just something about them. Send it to Sheps!

 

[drethib]

Ok sorry for the delay but thanks for all the feedback. I'll make these changes as soon as I'm confronted with the car this weekend due to being on the northslope for work. I'll post what outcome I get. A little off subject but recently I installed a 16G fully ported by myself. I added an atmospheric dump for the wastegate.after climbing to about 4 grand the wastegate starts to open and feels as if I'm losing power. Is it just an adjustment to be made on the wastegate? I know I should be able to bring my rpms higher than just 4 grand

 

[kottyking]

Yea its not the clutch, its your syncros. Typical dsm problem.

 

[teamdsm95]

synchro. i had that problem on my 2g. PITA and expensive.

 

[skatershawn]

ok sorry to steal a thread... but im in the spot on my rebuild where im flushing the tranny and adding new oil! BUT Royal Purple is a NoNo??
and is Pennzoil syncromesh stocked on most shelfs at auto stores!

 

[kottyking]

At my local parts stores, they do stock the synchromesh. I use redline in mine, no problems here.

 

[My1GLaser]

ok sorry to steal a thread... but im in the spot on my rebuild where im flushing the tranny and adding new oil! BUT Royal Purple is a NoNo??
and is Pennzoil syncromesh stocked on most shelfs at auto stores!

I don't like synchromesh either personally, but yes it is stocked at adv auto. I prefer Redline.

 

[99rtguy]

hmmm, this thread is what i need to bandaid my 2nd grind! .

 

[drethib]

ok with the synchros being a canidate for disaster what kind of labor goes into repair and cost?

 

[drethib]

I guess I could look through a manual but just some heads up would be nice

 

[My1GLaser]

I believe you can get a synchro kit from Mitsu for about $300. However this is the price I found for doing a double synchro upgrade using OEM components, so maybe the complete single kit is about half that???

It is a complete tranny disassembly/rebuild if that is what you are asking. Don't know what the labor at a shop is, but I imagine around $1000 since you can get an economy Jack's tranny build for $900.

 

[->PrOjEcTGS<-]

ok with the synchros being a canidate for disaster what kind of labor goes into repair and cost?

Ha... it's a '90 trans... If you're looking for upgrades such as a double synchro 2nd and a 4 spider center diff it can get quite expensive for a 1990- early '91 22 spline trans. They use a different gear setup than any of the other years. The edge of the gear is thicker than the other years and will NOT mesh with them. Therfore if you wanted to build a double 2nd trans you would have to swap to the newer input and intermediate shafts. Plus you'll have to swap in the matching center diff. It gets expensive really quick.

Now, if you have someone else do the work for you who can machine the gears to accept double synchros then that's generally cheaper. In all actuality going back with just a stock rebuild on a 1990 trans is the cheapest way out. If you want any upgrades it's cheaper just to buy a good 92-99 core and get it rebuilt instead.

Trust me I'm dealing with the same situation right now as we speak. Early 91 trans trying to see what parts will work in the 92-99 trans. Not Many... But to put it into perspective I just spent $325 at MitsubishiParts.com on:

1st gear synchro -
2nd gear double synchro
2nd gear
2 x input shaft bearings
2 x intermediate shaft bearings
3-4 shift fork
1-2 shift fork
3 roll pins

If you went with the stock single synchro parts it would be a lot cheaper than that because the double synchro is 79.00 in and of itself whereas the stock part is only $20

 

[drethib]

Crap that is a B U M M E R ok appreciate the info that's wraps things up folks

 

[My1GLaser]

ProjectGS, you got part numbers for any of that? I have a spare 91 trans that I am wanting to build myself. Was yours a 22 or 23 spline shaft? Mine was 23, but I don't know if that means it was a late 91 and I am compatible with 92-94 parts or not? And from what I understand, I need a 93-94 shaft of some sort to do double synchro 3-4? I am running a 90 vr4 tranny right now, and I think it's 1-2 can be made into a double synchro?

I wish I knew more about what I needed, but mine hasn't broke yet so I really haven't needed to push the build yet.

 

[talondave]

If you want any upgrades it's cheaper just to buy a good 92-99 core and get it rebuilt instead.

92-96! The 97-99 has different gear ratio.

 

[->PrOjEcTGS<-]

92-96! The 97-99 has different gear ratio.

But if you use the matching T-Case it will work in any car.

ProjectGS, you got part numbers for any of that? I have a spare 91 trans that I am wanting to build myself. Was yours a 22 or 23 spline shaft? Mine was 23, but I don't know if that means it was a late 91 and I am compatible with 92-94 parts or not? And from what I understand, I need a 93-94 shaft of some sort to do double synchro 3-4? I am running a 90 vr4 tranny right now, and I think it's 1-2 can be made into a double synchro?

I wish I knew more about what I needed, but mine hasn't broke yet so I really haven't needed to push the build yet.

Yea, the original trans out of the car was a 22 spline early-91 model, identical to 1990's trans. If it was a 23 spline you're probably safe and it's more than likely a late-91. Unless of course they swapped the 22 spline shaft out for a 23 spline shaft to mate a new t-case on. (Unlikely)

The trans that I'm rebuilding is a 1995 2g trans. Here are the part numbers for a 2g trans that I listed above:

1st gear synchro - MD745477
2nd gear double synchro - MD745896
2nd gear - MD743572
2 x input shaft bearings - MD726235 and MD732314
2 x intermediate shaft bearings - MD726236 and MD736638
3-4 shift fork - MD746854
1-2 shift fork - MD723439
3 roll pins - MD701722

If you wanted to go with a double synchro 1st, 2nd, 3rd and 4th. I believe Jack can machine your '90 VR4 trans' original 1st and Second for the double synchros. For the double synchro 3rd and 4th gears you would have to get a new intermediate shaft. This is because 3rd and 4th on the input shaft will need to be changed out to the newer design for the double synchros and they won't mesh with your 3rd and 4th gears on the '90 intermediate shaft. Also, since third gear on the intermediate shaft drives the center diff you'll have to change out the drive gear on the center diff. All that and you'll be good.

If you want to do this all to the 92+ trans, all the double synchro gears should work fine in that model year. Then you can have him machine your 1st gear for the double synchro.

But, I believe Jack has the ability to double synchro 1-4 in the 92+ trans using your old gears. And I'm sure all other top shops do the same thing.