Lost Faith - 6SPD and toyota

The key to this and any manual tranmission is to match revs. The engine rev hang toyota has built-in is an asset to a long lasting gearbox if driven properly. Provided you double clutch, the resulting shift tempo allows a near perfect gear engagement. I'm to the point where i can sense when I DO IT WRONG and feel the synchos actually working. Mind you, there is not a grind when this happens, it just a tactile difference in engagement. By the same token, when downshifting you should also double clutch with a throttle blip in neutral. Downshift using the synchronizers on routine stops is abusive in my view. It is far better to just pop it into neutral and coast to a stop using the brakes.

For those that don't understand double clutching.... you clutch in and pull the shifter out of gear to neutral. You then release the clutch while the shifter is in neutral. (this synchornizes the engine flywheel speed to the clutch disc and thus the trans. input shaft speed) When the engine revs drop to the operating range of the next gear... push in the clutch and move shifter to next gear. (If done correctly, it will just glide in.) Finally, release the clutch and go about your business. It's all a timing thing.

I drive semi 300+ days a year. It changes the way you look at things when you have NO synchros. You soon realize there are 4 things that need to be rev matched for a shift to happen without grinding or synchro assistance... Flywheel rpm, Clutch disc/transmission input shaft rpm, Trans. gear rpm, and trans. output(road speed) rpm.

Those of you that are slam shifting your truck will have issues in the long run. The truck is too heavy to expect things to last with that driving style. Toyota knows what they are doing and the rev hang is there to slow down the shift. People with Nissans can brag all they want about shifting their xterra/frontier like a Z car.... Get back with them in 10 years and see how it is holding up then. I've had exposure to 6 Nissans and they are all had manual trans. issues and were just throw aways after 10 years. Toyota's are different.

If you aren't willing to drive it like a truck and accept the limitations therein... they sell auto tranny's all day long...

 

^^^ I'll wait for your throwout bearing chirp thread in a couple years. Every clutch throw wears that aluminum quill down a little bit more and more and more and more and.... well you get the picture, until you get the stainless quill sleeve and oversized TOB.

Another way to look at it... if your fluid gives crap shifting chances are your tranny is going to tell you later. All that waiting for the synchros to shift - that's not Toyota's way of telling you that you're not shifting it 'like a truck'. That's just synchronizers sliding under pressure for an extended period of time. Here's an alternate definition - excess wear. Just search for threads about 6 speed's synchros getting worn down to nothing and the tranny won't go unless the gear is skipped or double-clutched. I wonder why... in reality I'd conjecture that Toyota likely compared the cost of a specialty fluid factory fill versus how many of these will actually fail in the 60k powertrain warranty, and daggummit the gearbox lasted just a little too long.

Rev hang is there for NOx emissions, their words. There would be less drivetrain shock without it in most cases.

Actually 2 quarts will do it. If you buy 3, you can do the xfer case as well (between both you'll have a tiny bit leftover if you don't spill).

 

^^^ I'll take that throw out brg chirp over the crunch of the synchros anyday. I don't see how a "might have it/might not" problem with the tb system is relevant to a synchro issue.

With the rev hang these things have, i see no other way but to double clutch or at least slow down your conventional shift. Fluid may hide the problem...for awhile. If you shift fast tho, those synchros are working very hard, especially on the 2-3. When that input shaft and clutch disc are still zinging along, something has to slow it down, and that little piece of brass will hate life and you eventually.

I'll take the advise on the upgrade fluid tho... can't hurt to have extra insurance there. For now tho, i'm happy shifting it slow, smooth and ez.

 

Double clutching was the old non-synchromesh days back in the 1940's. I bang through the gears fast, I shift with authority and the MT likes it. I don't fuck around shifting, I bang through the gears as I please and the MT responds beautifully.

 

Do what you want. It's your truck. I've been there and done that too and it's fun... I'll grant you that.

I'm just giving an option how to drive it carefully for the long run. I have a 10 year outlook on a vehicle and i paid cash for this buggar.

I'm know i'm off the bell curve of normal on this one. A million miles in a non-syncro semi tractor transmission changes a guy. Proper shifting becomes a demand...kinda like breathing.

 

For what it's worth... My truck has 44k miles. The first throw out bearing went out at half those miles.

I agree with the slow shifting for daily driving, that little pause in neutral really cuts down on synchro stress. Almost like float shifting just with the clutch used for good measure. I just don't double-clutch it on upshifts like when I first got it. Downshifts I'm more careful with. If it's within a few hundred rpm I'll just blip the throttle in neutral, anything more is double-clutching territory.

I have a few close family members that have driven big rig for years, I've been coached in the no-synchro drill I just cheat a bit because I have them.

I am guilty of once in a blue moon romping on it and making that #2 synchro work a little hard but it's rare. It's the guys that do it half the time or more that wind up with tranny issues well before there should be.

 

There are some good boxes and some bad boxes. I thought mine was out of a willys jeep until I got fluid into it that let it work as designed. It was doing lots of stupid stuff... it would lock me out of 1st at a standstill, it would grind 4th and 6th at least once a day, shifting 2nd to 3rd only ever happened if double-clutched, etc. I had to treat it like a tractor box, no two ways about it, until the MT90 went in.

Glad there's at least some of these trannies making it into the greyer years without too many issues.

 

Sigh.......


I'd much rather Toyota send a mechanic who has torn apart a transmission, diagnosed, and repaired it before, come down to the dealership and tell me what is and is not normal. Being a PART of an engineering team does not make you qualified to diagnose and repair problems in multiple areas of a vehicle or anything else mechanical. There are engineers out there with tons of mechanical experience before and after earning those degrees and/or passing the PE exam. They are few and far between. The rest of them know their one specific specialty well, and after that it gets very iffy. An ME might design and test gears all day long, and not know a damn thing about gaskets. A mechanic typically does not have such a narrow scope, or a high and mighty attitude, either.

Where does my poor attitude towards your profession come from? I'm an appliance repair technician. I've grown tired of my customers spouting off with "I'm an engineer, and I don't think you've got this diagnosed right!" Really? Well then, I guess you don't need my services then. WHY did you call me? Clearly you've got this under control! Too many of you guys act like you're God himself, then when it comes down to experience and specialization, all of a sudden you have to call in someone else to fix your relatively simple household goods. But hey, I'm not smart or important without that pretty piece of paper hanging on the office wall, eh? Everything I do is guaranteed in writing for a good long time, if you think I'm wrong, sit back and let me prove it.

A mechanic, with or without the title "engineer", who goes around to Toyota dealerships and drives Toyota vehicles around all day long, has a pretty damn good idea what is "normal" in those vehicles. An engineer, with a degree and a PE license, who does the same thing all day long, will also have a pretty damn good idea of what is "normal" as well. Neither person is less likely to lie, or or give away Toyota's money trying to fix a problem that may or may not exist. Both will be influenced by the corporation they are working for. That doesn't make anyone smart or important, dumb or insignificant. They are the face of the corporation while they are out doing that job.

I agree, the definition of the word "engineer" does not fit someone who is a career automobile technician, and has not completed a course of academic study in the practices of engineering. Perhaps the reason why we are seeing corporations apply that title to folks who normally would not be using it, is the general public's perception of "mechanics" and "technicians". NOT ONE of my customers respects my knowledge and professionalism in my field. They all want an "engineer" to show up and diagnose their problem with their brand new, under warranty appliance. Toyota is giving the customer what they want: someone who can diagnose their problem and has the title that they associate with intelligence and importance.

 

Good info here

 

well guys, i wanted to update you on what i did. i traded the truck in on a 2012 4door tacoma with the auto, and i love it. thats what i should have bought in the first place. i only hard a difference of 4,000$ after taxes and tages from my trade and new price. i am happy now.

 

Definitely sounds like a syncro issue - Had the same thing happen on a '02 Mustang. How about trying to take it to another dealer and act like it's your first time getting it check out?

Maybe they will get a different "engineer" to look at it and he will agree with the problem.

There's a lot to be said for "playing dumb" to get your way - especially when dealing with these idiots.

Good Luck

 

Ha - just saw your last post. . . Congrats!

 

2006 DCSB 4X4 with the 6spd here... 125K miles and I haven't had any problems with the tranny, yet. Reading this, thought, I will be changing out the fluid for MT-90 post-haste.

 

The Redline website suggests the GL-5 gear oil for the transfer case and both diffs. Is that okay with the rear locker, or will it require an additional additive?

 

I think your question is answered here:
http://www.tacomaworld.com/forum/te...ging-differential-fluid-step-step-how-57.html

I would help you look but I'm at work.

 

You might want to call them about the Tcase. It does contain a synchro for the 2hi-4hi shift. I'm using mt-90 in both the transmission and the Tcase.

GL-5 is what you want in the diffs. No additive for the locker. Additive is only for the mechanical LSD. I haven't run the Redline in an LSD, so I don't know if the additive is needed. Many lubes that say "LS" on the bottle still need additive. If the LS groans and grabs in turns, then just add the additive. I do run Redline in my diffs but they are ARB's. Redline is my choice for everything except the engine oil.

 

+1

I do the same. Redline in everything except engine oil.

 

67000 km on my manual tranny so far and everything seems good! I find it shifts pretty good through the gears (running redline mt 90). The one issue i have with it is 1 in 100 times... from a stand still... i can't get the gear shifter into first. doesnt matter what i do. eventually it does or i just start in second. why is that happening??

 

Hey just curious if your clutch pedal still squeaks. If it still does, look at the two plastic pieces rubbing together. On the side that your brake pedal is closest to. Put a little lithium grease between them. Boom! No more squeaking!

QUESTION! Guys who have put Redline MT-90 in their T-Cases, has the shifting from 4 hi to lo gotten better? My t case is hesitant to switch between 2 4h 4L even while on flat ground... I am not a fan of electronic shifting! I prefer a stick t case shifter like the FJ's

 

I have redline in my t-case in an auto and I had redline in my t-case and tranny in a 6speed and I also have redline in my t-case and tranny in a fist gen. Yes, hi to low is smoother.