feynman314

I just got a 2006 TL 6MT and it runs and feels great...aside from 3rd gear being a little temperamental. Sometimes it just doesnt shift smoothly into 3rd and it will spit out of gear and make that nasty high pitched grinding noise. Sometimes its completely fine. All other gears are perfect.

Ive heard of people mention using different transmission fluid to help with that.

Any suggestions??

anx1300c

iTrader: (2)

You need GM Syncromesh fluid. Around $40-45 for three qts at your local GM dealership and your issues will be a thing of the past.

justnspace

iTrader: (1)

gm syncromesh solved my 3rd gear pop out!
i change it every 30k miles!

feynman314

awesome! thanks guys

komet

Feynman314,

If you're looking for a place online to buy the GM Fluid, get it here: http://paceperformance.com/i-7335347...d-1-quart.html If you choose to buy it from somewhere else, make sure it's named "GM Synchromesh Transmission Fluid -Friction Modified".

The website shows AC Delco bottles, but the actual fluid will come in GM labeled bottles. Shipping to me (in MA) costed $10, for about $45 in total.

If you change the fluid yourself or have someone else do it, make sure to check (or have them check) the old fluid for metal flakes. Chances are everything is fine, but the amount of metal flakes will tell you how well the original owner took care of the transmission.

And as Justnspace said, a fluid change interval of 20,000 to 30,000 miles should be fine.

NvrDwn

Yup same here the GM syncomesh solved my 3rd gear issues. Cost me $45, and it's as easy as changing the oil.

feynman314

GM Synchromesh MT Fluid ordered! Seems like everyone agrees on that remedy. Ill let you guys know how it goes.

Thanks again.

3rdGenHybrid

I don't approve of gm synchromesh fluid. I rebuild these transmissions all the time, and if you saw what this fluid does to the carbon on the synchros you would stop using it too. It remedies the issue because it swells everything up in the transmission. I've first encountered this with my 3G tls , tried it to see what all the rave was about because I didn't want to take the trans out in a then new car. It worked great! Until I started getting a bearing noise from the trans(may have not been related to the fluid) so since it was in warranty I had Acura take it out and replace the bearing. That's when I realized what this fluid did to my synchros. It pretty much turned it to mush, ended up replacing all the gear sets and still had a trans noise after. Long story short, just get the updated 3rd gear set. Turn around time is usually a day or two if you find a dealer who knows what they're doing. I do 8th gen si tranny rebuilds pretty much every other week, and the updated gear set is a guaranteed fix. Just my point of view and experience with gm synchro mesh fluid.

Adobeman

Interesting post. I have to say that you are the first person I've seen post such detail about negative thoughts on the fluid. There's certainly been lots of debates on principle (as in "damn it, I don't care if the GM stuff works, I shouldn't have to use it, Acura should fix it, they suck, wah wah wah....) but little in the way of "here's what I see it do to the insides". We've even seen one or two tests of it after use that didn't look alarming.

I don't dispute what you say but will say there are a huge amount of miles on many S2000 and 3GTL cars with the GM SM FM fluid. Many are members here so I do believe if there was something absolutely horrible it was doing we'd be hearing more about it.

I'll put one last thought out there. The OP is out of warranty so what's an updated gear set going to cost to get installed (assuming OP can't or doesn't want to DIY)? What's the risk that might be done incorrectly? And what's the cost of drain/refill with the GM fluid? My bet is changing the MTF is far, far, less $ and very well could defer any need to tear down the transmission for many years or perhaps even until the OP no longer owns the car. As an engineer I all too often use "absolute correctness" as a basis for decision. As I get older I've learned to make cost/benefit/risk also be a big consideration.

3rdGenHybrid

Definitely cheaper and cost effective vs a tear down. And I'm not saying this fluid will blow up your transmission, just simply sharing from what I've seen, what it is actually doing. I'm sure there's dozens of people who use this stuff and have no issues, but I'd rather be rest assured I resolve a problem by fixing it properly vs a band aid. A typical transmission rebuild on a 3G TL, dealer ship wise is mighty expensive, especially out of pocket. Between $1,200-$1,800. So I can see the issue with money. But I would rebuild it for a fraction of the cost. $800 with parts. Still pricey but it's about the same cost as a timing belt water pump. So it's not that much if you step back and look at it.

komet

3rdGen,

First, let me rant a bit. If you don't mind, I have some questions for you after my mini-rant. I would really appreciate hearing from someone such as yourself who has experience working on gearboxes.

I agree that the GM fluid is not a great alternative. I do not have any experience rebuilding transmissions, but I have done a lot of reading about both the workings of manual transmissions and people's experience with the GM fluid in both our cars and other Hondas. As you already know, throwing transmission fluid designed for one application into another application is pretty silly. Designing a transmission fluid isn't as simple as "lets make the most reliable, strong, yet viscous fluid out there." There are just too many variables to balance and such an ideal, while possible in one application, will not necessarily work in another.

In my "research", I have noticed that many people point out that the friction modifiers make too much heat and cause the fluid to degrade earlier than expected. Of course, if you ever dare to make a thread here and ask how people have fared in the long term with the fluid, they will flame you. This of course makes gathering real world data pretty frustrating and makes it even more difficult to collect accurate information. As Adobeman said, trying to find any real information such as tear downs or even just pictures of used fluid is very difficult.

That said, it's very rare to find people on this board who have first hand experience with rebuilding any Honda manual transmission, let alone ours. Thus, do you mind if I ask you some questions? It would be great to hear an opinion from someone who has first hand experience with the matter. I am sure other forum goers would appreciate you documenting your experience. Also, it is not often that I get to pick the brain of someone with experience rebuilding manual transmissions haha.

• First, do you know why the GM fluid causes such issues as the one you had? For example, is it the friction modifiers causing fluid degradation? Or is it just not designed for higher engine input speeds?
  
• What do you mean by "swelling"? Is the fluid not compatible with the metals in our transmission?
  
• Also, how similar in design is the 8th (or any) gen Si's transmission to ours? Is our transmission a "one-off" design, or was it more or less ripped out of the Si?
  
• What fluid do you recommend we run for our transmissions instead of the GM fluid? Is a synthetic fluid a good idea, or do they not create enough friction for the synchros to function properly?
  
• Two somewhat off topic questions: I have seen in diagrams that the TL's transmission has some kind of pump. Is this driven by the input shaft? Or does it only function when a gear is selected and the clutch engaged?
  
• And lastly, what is the best way to warm up the TL's, or any, manual transmission in cold weather? Where I live, I see some pretty high and low temperatures throughout the year ranging from 90 to 20 degrees Fahrenheit and below. In the coldest weather, it is easy to tell through somewhat harsh engagement that the synchros in the TL and our S2000 do not like being cold. Is it better to hold onto gears for longer than normal to reduce wear on the synchros and let them warm up? Or is it better to get up to speed and let the final drive in the TL's transaxle warm the fluid up?

I apologize if you have been asked these questions before - I am sure your knowledge has led to people constantly bugging you about such things as I am.

Btw, I am currently running the GM fluid. I realize this may very well lead to my transaxle going boom down the road, but worst case scenario is that I get to tear it down and get some experience rebuilding a manual transmission. I have tried other fluids for short periods including Penzoil MTF (was supposed to be Torco MTF, but that's another story) and Amsoil MTF. The Penzoil was fine but I could tell it wasn't as smooth as the GM fluid, and the Amsoil MTF was terrible in cold weather. I wouldn't be surprised if I ****ed up my synchros experimenting with fluids, but like I said before - if goes boom, then I guess it's time to learn something new (for Science!!!).

nt650blue

Wanted to weigh in on this. Our 2007 TL-S, purchased about a year ago, had the same 3rd gear popping out issue. Finally got around to trying the GM Syncromesh a month ago, and...holy cr@p! It's like a new transmission! Not a single pop out since, and shifting is much more fluid (pun intended) than before. Also have a 2004 Honda S2000 that I picked up last December, which has "crunchy" synchros in 2nd and 3rd. Changed out the fluid immediately with whatever Firestone uses, and I think things got crunchier. Ordered some more GM Liquid Magic from Pace (their shipping charges are excessive), had it changed today, and although 2nd is a tiny bit stiff, no more crunching into gear! This skeptic is a believer.

ZOMGVTEK

3rd is my best gear after GM SMFM, whereas I used to run into an occasional popout before on the Honda MTF stuff. Kinda odd.

My 6th is still a bit notchy, and I had difficulty getting into 1st twice in very cold weather. Not sure how normal that is, or how much popping new syncros in will help. I usually double clutch past 4th and 5th into 6th and it practically falls into gear if done right. However, going from 5th straight into 6th is the hardest of all engagements. Still not that hard, but worse than every other gear.

feynman314

Yeah, typically 3rd gear is always my favorite gear. Nice for cruising at high rpms and its just waiting for you to punch it and get moving. But, with this 3rd gear problem, I havent even really been able to enjoy it to the fullest.

My fluid says its shipped, but havent received it yet. Ill keep ya posted...