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05XT, 2 DC Audio Lvl3 15", DC Audio 1.2k monoblock, DC Power 270AMP alternator, SUMO 2in. lift,
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Discussion Starter #1
Hello all!

This is my first post on here, and actually the main reason I joined in the first place is because my XT 5EAT has been giving me headache after headache, and I am hoping to hear some advice or info regarding my issue. The car has 151500 on the clock, and I've owned it for a little over a year. I have some of the previous work done by other owners, and from the looks of it the fluid was changed regularly. I have heard that these are really robust trannys, especially if they are maintained well. But so far, I disagree.

THE ISSUE: Harsh shifting from 1st to 2nd, and 2nd to 3rd when in D (other gear changes are smooth as silk), if I am in manual mode, every gear shift is harsh to some extent. There are no codes and no money light. It does it really bad when I first drive it in the morning and it is cold, it seems to do a bit better when warmed up, but still will shift harshly most of the time. The way I compensate for it is I try to keep the RPMs as low as possible in 1st and 2nd, because of how harsh the shift can be sometimes. Sometimes it is so harsh, that I can hear interior panels bang against each other, kind of like going over a bump in the road.

WHAT I'VE DONE: A tranny shop had the car for about a week, and could not find any issues regarding the mechanical operation of the transmission (I was suspecting a pressure control solenoid, or a valve body issue), and suggested a flush my help the valve body if it is clogged. The flush was performed, with some extra additives, and it did not help. I then took it to a dealer, and they flat out told me that the transmission needs to be replaced. I took it to ANOTHER transmission shop for a THIRD opinion, they also said I need to replace it and that it is slipping, even though I have never experienced it slipping, and no other shop has told me it is slipping. However, in a recent visit again with first one (which I do trust the most), they told me that another Outback AT with a somewhat similar symptom as mine was reflashed by a dealer and the problem was fixed.

So my question is, could it be that there is a software bug in the TCM that is causing my harsh shifts? And perhaps maybe I don't have to replace my trans? If the reflash doesn't work, I cannot afford to replace the trans, so I would hate to get rid of my car because of the tranny.

Any info is greatly appreciated!
 

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2001 VDC/SC One of a Kind
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12,158 Posts
Some things come to mind.

Transmission mount may be worn/damaged/broken and the transmission is kicking around.

Lower control arm bushings also come to mind, but with this you would have some noise and maybe pulling on and off throttle.

TPS operation, or, the throttle body has a lot of carbon build up effecting TPS.

Accelerator pedal sensor errors.

Pressure switch 4 and/or 5, but both going to crap simultaneously would be odd.

Any of the speed sensors that feed to the TCM (vehicle speed and turbine speed)

Bad ground, weak battery, or a combination.

Has anyone checked the TCM for codes? You could have codes in the TCM and the MIL won't come on. It may also be that the computer(s) are not picking up on a problem because the gear ratios are correct (which throws the slipping suggestion out of the water), which leaves something other than the geartrain in the transmission.

You could try a battery disconnect to reset the TCM and it will revert to a base shift map until it learns otherwise after you drive it a while. The TCM is adaptive like the ECM and will change it's shift map according to how it's driven. Disconnect both terminal and touch the cable ends together for a few minutes and hook the battery back up. Or, find someone with the software in a scan tool that can communicate with the TCM and reset it that way.

If there is a problem in the valve body that has the pressure too high, you would replace the valve body as a complete unit. Doesn't take long to do it, but the valve body can run a few hundred plus labor unless you do it yourself.

Here's a good video on valve body replacement:
 

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05XT, 2 DC Audio Lvl3 15", DC Audio 1.2k monoblock, DC Power 270AMP alternator, SUMO 2in. lift,
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Discussion Starter #3
Some things come to mind.

Transmission mount may be worn/damaged/broken and the transmission is kicking around.

Lower control arm bushings also come to mind, but with this you would have some noise and maybe pulling on and off throttle.

TPS operation, or, the throttle body has a lot of carbon build up effecting TPS.

Accelerator pedal sensor errors.

Pressure switch 4 and/or 5, but both going to crap simultaneously would be odd.

Any of the speed sensors that feed to the TCM (vehicle speed and turbine speed)

Bad ground, weak battery, or a combination.

Has anyone checked the TCM for codes? You could have codes in the TCM and the MIL won't come on. It may also be that the computer(s) are not picking up on a problem because the gear ratios are correct (which throws the slipping suggestion out of the water), which leaves something other than the geartrain in the transmission.

You could try a battery disconnect to reset the TCM and it will revert to a base shift map until it learns otherwise after you drive it a while. The TCM is adaptive like the ECM and will change it's shift map according to how it's driven. Disconnect both terminal and touch the cable ends together for a few minutes and hook the battery back up. Or, find someone with the software in a scan tool that can communicate with the TCM and reset it that way.

If there is a problem in the valve body that has the pressure too high, you would replace the valve body as a complete unit. Doesn't take long to do it, but the valve body can run a few hundred plus labor unless you do it yourself.

Here's a good video on valve body replacement:
Thank you!

I am wondering if it could be a transmission mount, since there is some vibration from the car when stopped in gear when it's cold but not in neutral, but seems fine when the car is warmed up. And i just had the car inspected by a dealer and they said the engine/transmission mounts were fine. And wouldn't bad tranny mounts cause this to happen in all gear changes?

I have definitely tried the battery reset method, leaving the battery disconnected over-night and touching the cable ends together. It did not help.

I am not ruling out the TPS, accelerator pedal sensors, speed senors (vehicle and turbine), or the weak battery. I am not sure what the pressure switch 4 and 5 are :)

Some more info on the battery situation: I do have an aftermarket audio system in (about 1700W RMS), but I have upgraded the battery, alternator, engine ground, battery ground, and charging wire to the battery and these upgrades are supposed to be sufficient for the power I am running. But perhaps it still is messing up something with the TCM because of voltage drop? But I would think the transmission shops and dealer that I have taken the car to would've found something wrong with that and the other stuff you mentioned above (especially the dealer and checking for TCM codes, they definitely should've found codes if there were any, I paid them to do a tranny diagnostic).

One last thought: I know that the diffs have never been serviced, the car has never been used for towing, but maybe it could be a problem with the diffs?
 

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Premium Member
2001 VDC/SC One of a Kind
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Vibration stopped in gear is generally one or both of the front cv axles.

Pressure switches 4 and 5 are on the valve body in the transmission.

Yes, if there is insufficient ampere flow, things act up.

The techs at the dealership and some shops don't necessarily think about the small stuff that create what seems to be large ones. Grounding and battery issues cause all kinds of things to pop up. Automatics get burned up due to bad grounding and weak batteries.
 

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05XT, 2 DC Audio Lvl3 15", DC Audio 1.2k monoblock, DC Power 270AMP alternator, SUMO 2in. lift,
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Discussion Starter #5
Okay, so I may have a bad CV axle? The vibration definitely isn't there when the car is warmed up, only when cold. How else could I tell if I have a bad CV axle?

I may look into beefing up my already beefed up battery, or adding a second one. Is there a test that techs can preform that would tell them if there really is a lack of ampere flow messing up something in the TCM?
 

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2005 Outback Wagon 3.0 L.L. Bean
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556 Posts
You got it used and it always shifted aggressively? Maybe west_minist got a hold of it
 

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Discussion Starter #7
You got it used and it always shifted aggressively? Maybe west_minist got a hold of it
When I first bought the car, it did not shift aggressively or harshly, otherwise I would not have bought it. It started acting up when it started to get cold, (October of last year), I bought the car in July of last year.
 

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05XT, 2 DC Audio Lvl3 15", DC Audio 1.2k monoblock, DC Power 270AMP alternator, SUMO 2in. lift,
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Discussion Starter #9
Yeah just my luck 😂

I scheduled an appointment later today to get the TCM reflashed by the dealer to see if that helps any.
 

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Discussion Starter #10
UPDATE: Did get the TCM re-flashed, it did seem to fix the issue for a day or so. But now since it got really cold (I live in Colorado) it started jerking really hard in those first two gear changes again, so no fix :(
 

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05XT, 2 DC Audio Lvl3 15", DC Audio 1.2k monoblock, DC Power 270AMP alternator, SUMO 2in. lift,
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Discussion Starter #11
Still out of luck. I took it back to a transmission shop, they had the car for another week, and told me that the computer itself was telling the transmission to shift hard and late. They specifically told me that I do not need a new transmission, and that the valve body and solenoids were working fine. They said that the problem lies in the engine or engine sensors, but they could not find the issue because they do not have the equipment to "dive into" engine problems.

THIS IS LITERALLY A NIGHTMARE
 

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2005 Outback Wagon 3.0 L.L. Bean
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Is it a vibration? Shake the Prop Shaft and pay special attention to the rubber surround on the center carrier bearing.
 

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Discussion Starter #13
Is it a vibration? Shake the Prop Shaft and pay special attention to the rubber surround on the center carrier bearing.
I get a vibration from the car when I am stopped in gear (D or R) and the car is cold. When the car warms up (after driving on the highway for awhile) it no longer vibrates. I did just get my drive shaft replaced about a year ago, so should I still check that rubber surround?
 

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Outback 2011 3.6R Premium
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If you have a vibration when stopped and the transmission is in D then the first thing to check is the drive shaft, especially as you say it was replaced a year ago. If the replacements were not genuine Subaru drive shafts then they are very likely the cause of the vibration (as has been reported by many other members on this site).

If the transmission is shifting harshly when it is cold I would be suspecting transmission oil OR a sensor that is not reading properly when cold but OK when warmed up. Changing the valve body (with sensors) may fix this problem.

As you have found another transmission of the same model (referred to in a different post) I would consider purchasing the other transmission and swapping the valve body to see if this resolves the problem. This is much less work than swapping transmissions and much quicker.

Let us know how it works out.

Seagrass
 

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Discussion Starter #15
If you have a vibration when stopped and the transmission is in D then the first thing to check is the drive shaft, especially as you say it was replaced a year ago. If the replacements were not genuine Subaru drive shafts then they are very likely the cause of the vibration (as has been reported by many other members on this site).

If the transmission is shifting harshly when it is cold I would be suspecting transmission oil OR a sensor that is not reading properly when cold but OK when warmed up. Changing the valve body (with sensors) may fix this problem.

As you have found another transmission of the same model (referred to in a different post) I would consider purchasing the other transmission and swapping the valve body to see if this resolves the problem. This is much less work than swapping transmissions and much quicker.

Let us know how it works out.

Seagrass
Awesome, thank you very much!

Would an non-Subaru drive shaft still only cause the vibration when cold though? Because when the car is warm, it doesn't vibrate.

The transmission shop that looked at the car for over 2 weeks did not find anything wrong with any sensors or the valve body. I also did get the transmission flushed earlier this year. I may still swap the valve body and see how that goes. I will let you know!
 
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