4.6is transmission
 

Hi, the transmission in my 02 x5 4.6is with 128k miles started slipping today under normal driving conditions mainly between 3-4 gear. the worst was when I was accelerating up a hill moderately on the throttle and it slammed into 4th so hard I lurched forward. There's no messages on the dash nor any codes when my indy scanned it. Is my transmission on its last legs?

Thanks!!

It could be.

You could try a quick fluid and filter change, and see how that affects things. I get my stuff from The California Transmission Supply Company. Order an extra fill plug since they are cheap and just in case yours is bunged up or gets bunged up taking it out. Pretty easy procedure to do.

I think you have this transmission: 5hp24 transmission

I did a fluid and filter change about 5 months ago. So I'm not sure.

It doesn't sound like the torque convertor--usually a grinding/whining noise or vibration at certain speeds but no slipping is a torque convertor symptom.

Fluid could be low and it won't hurt to change it but once the transmission is showing failure symptoms a fluid change less apt to be the solution.

Your symptoms sound more like an internal problem--which does not have to be something that means a total rebuild but if that is the case that's what I would if it is torn down anyway. Internal issues don't have to break the bank.

Once you get the problem corrected I suggest adding Dinan transmission software that will make the transmission shift faster and firmer and carry a higher rpm in each gear. I think it contributes to longevity. I have a 4.6 and have many engine mods and at 110,000 mi. no issues.

I have an aftermarket warranty which has already covered an alternator so many I'll just go ahead and squire a new transmission... There's also some slack in the transfer case when accelerating.

That is a key piece of information that wasn't contained in your original post. If you hadn't done that, it would have been worth trying a fluid and filter change now. With that recent change, not worth doing another one. It is worth checking the fluid level.

If it was shifting fine before the fluid change, one option for you is to have the valve body looked at before pulling the transmission. The valve body contains actuators and hydraulic controls that if not functioning correctly, could cause the flare up you are seeing on the 3-4 shift. Recommend you don't drive for any length of time with it not shifting correctly, due to the potential for further damage from slipping and overheating.

But if it is covered by an extended warranty, just have them fix it. Doesn't really matter what is wrong as long as they are willing to cover it.

Most likely a bad o-ring. Do a search on this website and you will find people with similar symptoms and their fixes.

See this link for the o-ring:

http://www.xoutpost.com/953083-post29.html

It has done it since I bought it in February... I'm thinking just have a new tranny installed and get my money out of that rip off warranty company.

So it was doing this "Before" the fluid change. There goes that theory or assumption that the trans will crap out on you after a fluid change, or maybe not.

Yea, it's done it since I bought it with 117k but today it's really gotten worse.