Second gear

Ok guys need ur help when I start up my Jeep cold and take off it doesn’t want to go in second gear without grinding but after it warms up it shifts fine i just put a new clutch in it early spring any ideas?

 

When I put the clutch in

 

If it was a synchronizer it would be all the time. I guess it does have a synchronizer right?

 

10-4 thanks

 

I'm not one of those knowledgeable dudes but since it seems to be fine warmed up try some synthetic MT fluid? Right MT oil viscosity? Selectively occurring with 2nd gear leads me to think the problem may not be just the MT fluid ---subscribed

 

I put synthetic Lucas oil in it when I replaced the clutch and I’m going to check with the transmission shop and see what they tell me the jeep has 120000 miles on it witch I didn’t think was too bad and I’m pretty sure it’s been pretty well takin care of from the looks of everything else. But thanks for the help we’ll see what happens. Merry Christmas to all.

 

It does sound like a Synchro wearing out, but It might be an oil viscosity thing going. Which Oil did you use. 75w90, 80w90, or 75w140 etc. If your are not already running it you might try the 75w90 and see if that helps things. I strongly suggest running Redling MT90.

 

I think 75/90 but I’m not 100% sure thanks

 

.If you used GL5 gear oil, drain that mess out of there immediately!!!! GL5 will eat the brass synros in the AX5/AX15 transmissions because of the sulfur content. GL4 or full synthetic 10w30 motor oil is what is recommended by Chrysler and Aisin Warner (the manufacturer). Since GL4 gear oil hasn't been produced for a few years now it's very difficult to find. Many claim that Redline MT90 works well, it's only available online https://www.redlineoil.com/mt-90-75w90-gl-4-gear-oil or some high end speed shops, I use full synthetic 10w30 in mine with no problems.

You could try shifting a little slower when it's cold so the syncros have a moment to do their job. Once again if you used GL5 gear oil drain it immediately!!!!

 

Thanks I will find out for sure. Thanks

 

Lucas synthetic is GL5 according to the Technical Data Sheet https://lucasoil.com/pdf/TDS_Lucas-Synthetic-SAE-75W-90.pdf

 

Pretty sure it was GL5 synthetic 75/90

 

Well, after experiencing hard shifting I started looking up this for myself and get some very convoluted answers, everything from the Chrysler dealership saying the manual says 75w90 gl 5 to regular transmission fluid to 10 w 30 like someone else posted here, how about Royal Purple 75w 90, it says gl4 or 5 compatible, also says wont harm soft yellow metals, non corrosive. Very confusing subject!

 

Agreed. But when all else fails. What does the manual say? Just my opinion. You should always stick with what is recommended. Even if you use a full syn. Use the same weight oil / lubes. I am in no way an expert. But I did sleep in a Days Inn last night. .

 

What you read in the Owners manual that GL5 is recommended by Chrysler for the AX transmissions is a misprint, which was later corrected in a Tech Bulletin. If the dealership is telling you that, you best tell them to do their homework and not take your rig to them. 75w90 GL3 or GL4 and full synthetic 10w30 motor oil are the only recommended oils by Chrysler and Aisin Warner (the manufacturer) for those transmissions.

Now if a GL5 oil does state on the bottle that its safe for yellow metals like Royal Purple Max Gear does then yes,it's OK to use in the AX transmissions. I would be sure to read the bottle though just to be sure.

"Royal Purple Max Gear is recommended for use in truck and automotive front or rear differentials, manual transmissions and lower gear units of marine engines that specify use of an API GL-5 or GL-4 fluid. It is non-corrosive to soft yellow metals (brass, bronze, copper, etc.) and synchronizer safe." http://www.royalpurpleconsumer.com/products/max-gear/

You can also use Redline MT90

I just have a hard time paying double for something that isn't going to work any better. Royal Purple cost $88 , Full synthetic 10w30 $40 at least that's the cost out of my local parts house.

Bob, if you're referring to the difference between gear oil and motor oil. The viscosity of those two oils is measured differently. The viscosity of a 10w30 motor oil is the same as a 75w85 gear oil. Here's a chart that shows that

 

The only thing I’ve read or heard about using 10w 30 is it breaks down quickly, in other words you have to change it more frequently, however there is so much disinformation out I don’t know what is wrong or right! If I have to pay more for a oil that performs better I don’t care, what I don’t want is a oil that harms my transmission! Changing oil isn’t a problem either.

 

About once a year or 10,000 miles is all you need to change the 10w30 if it's full synthetic. Oil doesn't typically break down under normal conditions, we change it because it gets contaminated with things other than oil ie: water, wear metals, carbon, and what not.