1998 Tacoma 5-speed very notchy shifting

1998 5-speed 3.4L 175,000 miles

Brief recent history:

Replaced both master and slave cylinders on the clutch. Everything felt normal after that.

Replaced the transmission/gear oil about 5,000 miles ago with Royal Purple 75w90. Seems like since then I noticed that the shifting is very "notchy" especially when cold. Once it warms up a bit, the shifting seems to get better.

For the first time ever it actually grinded when downshifting from 3rd into 2nd.

Is this mere coincidence? Should I change the gear oil to something different? Should I check the shifter seat bushing thing?

Thanks.

 

i had the best results with redline mt-90 in my old 5sp tacoma.

 

Amsoil is all I ever ran in manuals and it got rid of the notchy feeling in my old Honda and a Honda has a pretty smooth shift.

 

I tried finding Amsoil locally and can't find it. Who sells it? Or do I have to order it online

 

There's probably a local distributor. Look on Amsoil.com for locations.

 

Not sure what you mean by "notchy".

Is it in the gears or in the shifter slot?

The only reason you'd need to mess with the shifter bushing is if you feel that getting the shifter into the slot isn't crisp. Takes 10 minutes to pull so really easy to pull it and check. Looking to see if the nylon ball on the end of the shifter is smooth and not very worn. Pulled mine at 100k miles and compared it to the replacement one I had bought. Still looked like new.

75W90 is the right viscosity so wouldn't expect that to be the issue.

Not sure how long the synchros usually last on these transmissions but that'd be the first place I'd start researching if I got a bit of grinding with the clutch fully disengaged.

 

Definitely feels like in the gears.

And synchros was my first thought, but I'm not about to take on that endeavor.

It just seems too coincidental that as soon as I changed the gear oil in the tranny, I started to feel a noticeable difference.

I will probably go with some Amsoil (heard a lot of good things about it) and see if that makes it any smoother.

 

well by notchy do you mean harder to get it in gear? almost needs like a push?

My 1st gear is always like that when rolling a bit or down shifting. Of course all our 1st gears are like that due to the way toyota made the synchros on it. But if its doing it in a lot of gears all the time..id say it is the synchros..could be the oil but i dont see how..

often though just a blip from the throttle while downshifting allows your to shift no problem..

 

It's mostly 1st to 2nd and 2nd to 3rd. Then 3rd down to 2nd.

I've put over 150,000 miles on this truck, it's definitely acting different. Especially when cold. When cold I can barely put it in reverse or first from a dead stop.

 

the reverse thing is common. Ben, Jon and I have it i know. takes me a few tries usually for reverse.

Interesting though..i know the r150 is a pretty stout tranny though so..idk..be interested to see if the oil makes a big change. I remember when i changed the oil in mine at like 103k it seemed a lot smoother..didn't last though..

 

Yeah I'm going to get some Amsoil severe gear (or whatever it is) and see if that makes a difference.

I'll update.

 

I don't think I would put in severe gear. It's some good stuff for the diffs though. I would do this:
http://www.amsoil.com/shop/by-produ...-transmission-and-transaxle-gear-lube-75w-90/

 

My last transmission had a slight grind into 3rd(at redline) and after I installed a shortshifter it went away somehow.
I also noticed a big difference going from stock fluid to Redline MT90. I switched to Royal Purple because I didnt want to wait on shipping and it was ok at first but it definitely wasnt as good as Redline.
As soon as it started getting colder I started experiencing the same issues as you. I replaced it with Redline again( a month ago) and noticed a very nice improvement. I am waiting on my Marlin Crawler shifter base bushings, they really help.
I reccomend switching to Redline fluid and getting the shifter base bushings replaced. It does make a noticeable difference.

 

Notchy shifting is common for people who put GL-5 spec gear oil in manual transmissions. You should use a gear oil that's GL-4 spec ONLY, like Red Line MT-90, not a combo GL-4/GL-5 like most gear oil you'll find at the parts stores (including Royal Purple MaxGear). The sulfur additives in GL-5 can degrade your synchronizers.

 

Thanks ISU, Mitzu and bbob.

I remember posting a thread asking about what gear oil to go with and it was overwhelming. Granted I chose Royal Purple because it was in stock on shelves around the corner and on sale. But I remember reading that it would be fine for the brass synchros.

I will either get that Amsoil ISU listed (GL-4 only) or Redline MT-90.

I will update this thread after I get around to switching it out.

 

On more question:

Would running the Royal Purple for 10,000 (give or take) ruin my synchros permanently or is this something that might go away once I get the new gear oil in the gear box?

 

I remember going through the same thing on gear oil. I know I had it resolved to GL-4 and GL-5 for the tranny and diff, but don't remember which one went where.

I too have had a tough time getting mine into reverse ever since I've owned it, usually just letting the clutch out in neutral and then trying again will do the trick.

When exactly did you change the tranny oil? If it was right as it was getting cold out I might blame that, mine is harder to wake up in the morning than I am and protests shifting into reverse or first on first startup.

The sulphur has started eating your synchros. I'd say unless you totally flush it all out somehow you might be boned. I'm sure with less sulphur in the case it slows down a lot, but it will still be eating them at a slow rate.

 

X2 on the MT-90 great stuff, amsoil i really great to I use it in our work trucks.
I have the marlin shifter bushings, love them I have put them in every yota I have ever had.

 

On the Royal Purple Max Gear bottle it says it is non-corrosive to bronze synchronizers.

I would assume it does not have sulfur in it, but who knows?

 

+1 to what everyone else said about redline MT-90. My trans was really choppy/hard to shift when I bought my truck. It was even hard to go from 4th to 5th and vice versa. I switched to MT-90 and I haven't had a problem since.