Shifting gears feels rough
 

I noticed that shifting gears is becoming "rough" like I have to put more force into sliding it into 2nd or 3rd, etc... especially going into 2nd.
It feels even rougher under WOT, as if I have to yank it into the next gear.
Before the movements used to feel a lot smoother.... now I can feel resistance from the gear walls/doors or whatever their called.
The clutch pedal feels fine.

Are there any possible problems or is it just in my head?

Just drove again and noticed when I'm at a stop with the clutch fully depressed it shifts normally, when I'm accelerating, it gets rough to select gears.

How much play up top do you get with the clutch pedal? It should be less than 1" before feeling resistance. With brakes released, clutch depressed, get in 1st. Does the car "lurch" forward or clunk?

sub'd

Clutch pedal still feels fine and stiff. No my car doesnt lurch or clunk forward when going into 1st with brakes off. However there is a clunking NOISE going into 2nd, but after some research on the forums, people say its normal.

The 6 gears have walls that block you from shifting when the clutch isnt depressed. This is where im feeling resistance when the car is in motion, and it is a lot more noticeable going into 2nd and 3rd.

I spoke to a friend at work who has a 2010 Mustang V6 and he says he has the same problem.

Have you switched gearbox fluids yet? That's what I did, and it feels great. It's Redline synthetic. It's not even notchy anymore.

No, I bought the car recently, but its on my list of things to do soon. Flush all the fluids, etc...
Is there anything else that can be causing this? any major worries I should have?

Check to make sure you do have plenty of clutch fluid. Low level or gear lube are the only things I can think of that would change performance under moving and stopped conditions, other than syncros but that is highly unlikely.
How many miles on car?

I think worst case scenario is CSC going out, but I am thinking not. From what I understand that is an instant failure, not gradual.

I would lean with just changing gear lube. You will notice the difference.

Car has 48K currently.

Ive read on the CSC issue and it seems as the key point of failure is in the clutch pedal.
No sure what synchros are exactly.
And how much does a dealership charge to change out the gear oil? I will also do a transmission flush at the same time.

Just checked my fluids, both brake fluids are topped off and clear, so that cant be the issue.
Maybe it is the gear oil, but I really dont want to spend money on that if it isnt going to solve the issue. What if the previous owner changed the fluid not too long ago...

What if he didn't? If you didn't get full maintenance records from the previous owner, just change out all the fluids. That way you can track the maintenance intervals. Diff and tranny fluid shouldn't cost more than $40-50. DIY it, don't let the dealer do it.

The diff oil I can do, but the transmission fluid? is it just as easy? and dont I need a special vacuum or something to flush the system and get ALL the old fluid out?

Nope. Drain and fill just like the diff.

I will probably do the fluids on Monday or Tuesday. I will report back to notify you guys if that fixes my issue.

Redline MT 85 makes a big difference for the transmission.

Yep. Great stuff. Highly recommended. And redline for the diff too.

Thanks, Im guessing I can find those at Autozone right? or maybe Pepboys...

Highly unlikely. Order from Z1. Make sure you order 4 new crush washers as well.

Looking at the redline website, is the same gear oil used from both the diff and manual transmission?

Nope. MT85 for the tranny, 75w90 for the diff if remember right. There's a DIY here for both. Take a look to confirm the right weights and quantities before you order. Buy one extra each.

And the washers, 2 for the transmission and 2 for the gear, 4 total right? (just read the right ups)

Only thing is, I dont trust jack stands lol. What if the jack stand fail and I get crushed!

Jack stands are fine if you buy decent ones and put them in the right places. I've had more ramps fail than jack stands. And you need the car level to fill it right, so ramps are out.

Jack stands are fine as Chuck said. I just pulled my transmission on jackstand and only crushed my pinky. Follow the DIY and you will be fine. 10mm hex head socket( like an allen wrench) will be handy works on the diff too.

Remember to open the fill plugs before you open the drain plugs. You don't want to find out the fill is seized after you empty it out.

Guys, I dont feel like ordering these fluids online... I am thinking about getting Royal Purple at Pepboys. It seems to be just as good, and a little more expensive.
Any thoughts?

Order the redline online. Royal Purple isn't that great. If you feel like getting into the "why" of that, google "bob is the oil guy" and start reading. Redline, Motul or Amsoil for the diff and tranny.

I dont know, I think I will be stubborn and go with Royal Purple.
Also on a side note, on the Redline website both the gear and manual transmission oil is referred to as "gear oil" is it essentially the same thing?

Here is what I will be getting...

for the Tran Royal Purple Synchromax Synthetic MTF Quart | Product Details | Pep Boys

for the Diff Royal Purple Max Gear 75W90 Synthetic Quart | Product Details | Pep Boys

Go for it. There's only tons of information out there about why Royal Purple is garbage with a great marketing program. It's your car.

Go over to the forum I mentioned. It's eye opening. The right fluids cost a little more, but you only need to change them every 15-30k miles. Do it right the first time.

But should I use the 75W90 Gear oil for both the trans and diff? or should I use the other fluid for the trans?
Ive read several other websites saying that gear oil is used on both?

Do not run a 75 weight in the transmission. That's why the Redline is great. The transmission wants an 85 weight. Use MT-85 in the trans and 75w90 in the diff.

But I really wanna go with Royal Purple lol.
No store in Central Florida carries Redline and their company is based in California. Shipping is expensive for these fluids post 9/11.

So are the two fluids I showed you good for my applications?

No, but it's your car. I'm out. You've gotten plenty of good advice and you're going in a different direction out of laziness or cheapness. Z1 is in Georgia and carries Redline. Good luck.

Lol! Every single product has mixed reviews. You claim that there are many bad stories to Royal Purple, but Ive seen many good.
I dont know. Maybe I will order Redline from Georgia, but... What is the factory OEM specs for both oils? I thought it was 75W90 for trans AND diff...

Redline is what you want

/discussion

I'm not going off stories or reviews, dude. Bob is the oil guy is a forum, like this one, where fluid engineers debate these things. That is where you go for info, not online reviews. The factory specs are in your manual, but there is a very good reason we're all running MT-85.

So Redline MT-85 and 75W90 gear oil will eliminate my notchy, otherwise stiff shifting?

I have attached the recommended fluids per the FSM. They are not the same.

Chuck is pretty damn knowledgeable. I have done my research as well. You're getting some solid info here, but we can't force you to accept it as truth.

If you want to question why we all recommend Redline MT-85 over the 75W per the FSM, then maybe you can do the research yourself?

If the issue is fluid related, yes. If not you have to start looking at mechanical causes. But this is the most likely solution.

Not guaranteed, but it's a good start. Even if it doesn't, you are better off with it :twocents:

BTW, OP...

I responded to your post on the differential fluid DIY thread. You do not need an extra quart (2 is fine) for the diff fluid. However, the transmission fluid calls for 3 qt, and it is recommended that you get an extra. The fluid you're pumping into the transmission should come out the fill hole when full.