Tried GM synchomesh in my daughters Tacoma and it dramatically improved the notchy shifting and the ability to find reverse and the shift into first coming to a stop. Completely fixed all of that 100%. Had reservations about how light it was and drained and filled with Amsoil manual tran 75-80 gl-4 and the poor shifting is back. I have 100% complete faith that Amsoil is a quality transmission fluid but for some reason Synchomesh improves shifting in this particular 5-sp manual... just afraid of running that light of an oil especially with hot summer months coming soon. What ever is in this synchomesh fluid it diffenately improves shifting... one would think that something that improves shifting cant be bad for a transmission???
Poor shifting back with fluid change
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Why not just go with the GM fluid and call it a day? I wouldn't worry much about the summer months coming unless you plan on towing in extreme heat with the vehicle. I'm sure the GM fluid is fine for your application, and was tested by GM in hot as well as cold use.
I am still with my stock fluid. As the transmission has broken in, now 40K the shifting has improved dramatically. Second to first is not synchronized and should not be forced. At least on the 4cyl 5-speed. Mine will go in smoothly under 5 MPH unless it is really cold. I am planning on doing a change and probably go with Amsoil MTG from a dealer here on BITOG.
It can be bad. So you have improved shifting but your bearings and gears can see increase wear due to an overly thin fluid.
If shifting is that bad in a Toyota manual, something else needs looking into. I fill them with 75w90 and never have problems.
Bleed/adjust clutch. Inspect drive train mounts. Lube/inspect/adjust shift linkages/bushings...
If shifting is that bad in a Toyota manual, something else needs looking into. I fill them with 75w90 and never have problems.
Bleed/adjust clutch. Inspect drive train mounts. Lube/inspect/adjust shift linkages/bushings...
Undummy, I think some folks expect a truck transmission to shift like a Mazda MX-5 Miata, a shifter with true rifle bolt precision. But the Op may have a problem that needs rectified.
Bleeding the clutch might be a good idea. I just re-read this thread and would suggest going to an approved fluid, and make sure everything related to the clutch is in good working order. Does it grind at all going into reverse?
Originally Posted By: Blaze
What ever is in this synchomesh fluid it diffenately improves shifting... one would think that something that improves shifting cant be bad for a transmission???
Amsoil MTG is an approved fluid.
It can be bad for the gears and bearings, and still feel like it engages fine. It is interesting as you post this as we in WA state are in the middle of a snowzilla. You may not like the synchromesh in the middle of summer.
Here's what you may consider, but you didn't hear it from me: Mix Amsoil synchromesh MTF and MTG - maybe 50/50.
What ever is in this synchomesh fluid it diffenately improves shifting... one would think that something that improves shifting cant be bad for a transmission???
Amsoil MTG is an approved fluid.
It can be bad for the gears and bearings, and still feel like it engages fine. It is interesting as you post this as we in WA state are in the middle of a snowzilla. You may not like the synchromesh in the middle of summer.
Here's what you may consider, but you didn't hear it from me: Mix Amsoil synchromesh MTF and MTG - maybe 50/50.
Originally Posted By: Hermann
I Second to first is not synchronized and should not be forced. At least on the 4cyl 5-speed. Mine will go in smoothly under 5 MPH unless it is really cold.
There is (or WAS) a syncro on your transmission's second gear. If you can not make that shift "smoothly" even when cold, that second gear syncro is worn or damaged. Most if not all second gears are large and heavy and carry a good bit of rotational inertia...thus they demand a lot of syncro work to equalize gear speeds at the shift. They often show wear before the other syncros in a transmission.
I Second to first is not synchronized and should not be forced. At least on the 4cyl 5-speed. Mine will go in smoothly under 5 MPH unless it is really cold.
There is (or WAS) a syncro on your transmission's second gear. If you can not make that shift "smoothly" even when cold, that second gear syncro is worn or damaged. Most if not all second gears are large and heavy and carry a good bit of rotational inertia...thus they demand a lot of syncro work to equalize gear speeds at the shift. They often show wear before the other syncros in a transmission.
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Originally Posted By: ammolab
Originally Posted By: Hermann
I Second to first is not synchronized and should not be forced. At least on the 4cyl 5-speed. Mine will go in smoothly under 5 MPH unless it is really cold.
There is (or WAS) a syncro on your transmission's second gear. If you can not make that shift "smoothly" even when cold, that second gear syncro is worn or damaged. Most if not all second gears are large and heavy and carry a good bit of rotational inertia...thus they demand a lot of syncro work to equalize gear speeds at the shift. They often show wear before the other syncros in a transmission.
Good info ammo. If that's the case then double clutching might help. I had an old Chevy van with a three on the tree that I double clutched because of some transmission issues. I bought it that way for next to nothing. The PO had put a clutch into it hoping to resolve the problem, it didn't. I drove it that way for years, since it was a beater work truck and I wasn't going to put any money into it. I actually enjoyed driving it. LOL
Originally Posted By: Hermann
I Second to first is not synchronized and should not be forced. At least on the 4cyl 5-speed. Mine will go in smoothly under 5 MPH unless it is really cold.
There is (or WAS) a syncro on your transmission's second gear. If you can not make that shift "smoothly" even when cold, that second gear syncro is worn or damaged. Most if not all second gears are large and heavy and carry a good bit of rotational inertia...thus they demand a lot of syncro work to equalize gear speeds at the shift. They often show wear before the other syncros in a transmission.
Good info ammo. If that's the case then double clutching might help. I had an old Chevy van with a three on the tree that I double clutched because of some transmission issues. I bought it that way for next to nothing. The PO had put a clutch into it hoping to resolve the problem, it didn't. I drove it that way for years, since it was a beater work truck and I wasn't going to put any money into it. I actually enjoyed driving it. LOL
1st to 2nd is fine, it is downshifting to 1st while still still moving that is a issue. It is a common issue on the Tacoma forum I frequent. Mine and others on the forum have the same issue even when brand new. It is the design of the transmission IMO
Originally Posted By: Hermann
1st to 2nd is fine, it is downshifting to 1st while still still moving that is a issue.
Will double clutching help downshifting into first?
1st to 2nd is fine, it is downshifting to 1st while still still moving that is a issue.
Will double clutching help downshifting into first?
Originally Posted By: Hermann
1st to 2nd is fine, it is downshifting to 1st while still still moving that is a issue. It is a common issue on the Tacoma forum I frequent. Mine and others on the forum have the same issue even when brand new. It is the design of the transmission IMO
News flash, downshifting to 1st with any manual transmission is always difficult at speeds above 5-10mph. Teach her how to rev match shifts and it will be fine, just a tap on the throttle coming up to a stop helps select 1st. Secondly, GM Synchromesh's viscosity is about equal to a 5w30 oil, so its way thinner than 75w-90 and remember its winter in most areas of the country meaning the cold temps make the gear oil thick and thusly its harder to shift until its warmed up
Thirdly, its cool your daughter is driving a 5spd truck, keep up the good work
1st to 2nd is fine, it is downshifting to 1st while still still moving that is a issue. It is a common issue on the Tacoma forum I frequent. Mine and others on the forum have the same issue even when brand new. It is the design of the transmission IMO
News flash, downshifting to 1st with any manual transmission is always difficult at speeds above 5-10mph. Teach her how to rev match shifts and it will be fine, just a tap on the throttle coming up to a stop helps select 1st. Secondly, GM Synchromesh's viscosity is about equal to a 5w30 oil, so its way thinner than 75w-90 and remember its winter in most areas of the country meaning the cold temps make the gear oil thick and thusly its harder to shift until its warmed up
Thirdly, its cool your daughter is driving a 5spd truck, keep up the good work
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Originally Posted By: EricJRoy
News flash, downshifting to 1st with any manual transmission is always difficult at speeds above 5-10mph.
^^Exactly!
News flash, downshifting to 1st with any manual transmission is always difficult at speeds above 5-10mph.
^^Exactly!
Originally Posted By: Blaze
Tried GM synchomesh in my daughters Tacoma and it dramatically improved the notchy shifting and the ability to find reverse and the shift into first coming to a stop. Completely fixed all of that 100%.
The OP stated that the GM fluid fixed the problem with the fluid change. Now with the thicker fluid he has the problem again under the same circumstances. In this case double clutching going into first is worth a shot with the thicker fluid, as long as the OP isn't going too fast for the gear. I would also suggest when going into Reverse to stop completely, shift into first, then reverse. It will cost nothing to try double clutching to see if it makes any difference. As mentioned it could also be normal, its very hard to tell w/o actually driving the truck.
If I down shift into first I am usually going very slow. Depending on engine power and gearing second can usually do the job if the vehicle is moving around 5 mph in most cases.
Tried GM synchomesh in my daughters Tacoma and it dramatically improved the notchy shifting and the ability to find reverse and the shift into first coming to a stop. Completely fixed all of that 100%.
The OP stated that the GM fluid fixed the problem with the fluid change. Now with the thicker fluid he has the problem again under the same circumstances. In this case double clutching going into first is worth a shot with the thicker fluid, as long as the OP isn't going too fast for the gear. I would also suggest when going into Reverse to stop completely, shift into first, then reverse. It will cost nothing to try double clutching to see if it makes any difference. As mentioned it could also be normal, its very hard to tell w/o actually driving the truck.
If I down shift into first I am usually going very slow. Depending on engine power and gearing second can usually do the job if the vehicle is moving around 5 mph in most cases.
Originally Posted By: EricJRoy
News flash, downshifting to 1st with any manual transmission is always difficult at speeds above 5-10mph. Teach her how to rev match shifts and it will be fine, just a tap on the throttle coming up to a stop helps select 1st. Secondly, GM Synchromesh's viscosity is about equal to a 5w30 oil, so its way thinner than 75w-90 and remember its winter in most areas of the country meaning the cold temps make the gear oil thick and thusly its harder to shift until its warmed up
Thirdly, its cool your daughter is driving a 5spd truck, keep up the good work
Exactly. Rev matching is the way to go, even if you could do it without rev matching, that saves extra wear on your transmission, at least in the way of the syncros.
News flash, downshifting to 1st with any manual transmission is always difficult at speeds above 5-10mph. Teach her how to rev match shifts and it will be fine, just a tap on the throttle coming up to a stop helps select 1st. Secondly, GM Synchromesh's viscosity is about equal to a 5w30 oil, so its way thinner than 75w-90 and remember its winter in most areas of the country meaning the cold temps make the gear oil thick and thusly its harder to shift until its warmed up
Thirdly, its cool your daughter is driving a 5spd truck, keep up the good work
Exactly. Rev matching is the way to go, even if you could do it without rev matching, that saves extra wear on your transmission, at least in the way of the syncros.
Rev matching makes any shift smoother but it only helps out the clutch...you need to double clutch that downshift into first to help out the syncro.
I had an unsyncronized first gear on my first car..Austin Healy Sprite. Had to do a GOOD double clutch to hit first gear when moving!!! After a few months of driving I could hit first gear at almost any forward speed that was short of 5000rpm in that gear. The noise and vibration of that BL 4cyl helped a lot in that procedure. Notice how hard it is to drive a stick shift car that is smooth and quiet????
I had an unsyncronized first gear on my first car..Austin Healy Sprite. Had to do a GOOD double clutch to hit first gear when moving!!! After a few months of driving I could hit first gear at almost any forward speed that was short of 5000rpm in that gear. The noise and vibration of that BL 4cyl helped a lot in that procedure. Notice how hard it is to drive a stick shift car that is smooth and quiet????
Blaze, I am in the habit of selecting 1st before reverse gear, you always find it and it never grinds that way
Thanks yep that seems to work well... I have noticed with warmer weather now that Amsoil is working well. The Synchomesh is just plain awesome in real cold weathee.
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