Tranny Oil Report

I have a 2003 Reg Cab 4x4 2.7 4 Cyl.

At 35,000 I decided to change out the tranny and read diff fluids. On the recommendation of several threads here I chose Mobil 1 75-90 Synthetic as a replacement fluid for both.

It is now 5 months since the change.

I live in eastern Colorado where the winters can be pretty cold at times.

Before I made the fluid change the tranny performed normally as I would expect it to - no hard shifts, no grinding, no noise, etc. Didn't matter how cold it was.

Since the change and especially in cold weather the tranny shifts hard and I can feel the gears when shifting. It gets better as the tranny warms up. When stone cold the first shift from 1st to 2nd is next to impossible - I have to double clutch and finesse it to get it to shift smoothly. Even when fully warmed up I can still feel the gears when shifting into 5th for example.

I am worried that I am prematurely wearing out my synchros.

So to say to least I am very disappointed with Mobil 1 gear oil and will be changing back to OEM or equivalent (not sure what brand would be equivalent ???)

Any thoughts on this situation? Am I the only one who has had this experience? Why would the OEM oil be so much smoother than the supposedly superior synthetic ?

 

one of the confusing things is that many oil say GL-4 or GL-5.

it is hard to find straight GL-4 that is specifically NOT GL-5.

 

I put royal purple in mine and its doing the same. When its cold its hard to shift until it warms up. I dont know if it is because the oil is new or what. I think once it is driven a while might be ok. I would like to try amsoil but its not available in stores. Can you only get amsoil through a rep?

 

Try Redline MT90 in the trans and tcase. I know a lot of people run it (at least on TTORA) and for the most part are all happy with it.

 

This just happened to me...changed the stock gear oil out on my 09 Manual 6 speed and used redline MT90 75-90 and i have to say the stock oil was much smoother....anyone else notice this?

 

Are you saying that you used gear oil for tranny also? Cause if you did it's a huge mistake. But maybe I read it wrong.

 

i think he means manual trans

 

i used to work at a mitsubishi dealership,which mitsu had real notchy manual transmissions...the factory told us to use general motors syncromesh manual transmission oil...you wouldn't believe how big of a difference it made..i would use that or buy factory from toyota if u were happy before this