2009 XC90 Tranmission Service Urgent

[RickHaleParker]

He did say that it "could help or make it worse". Something about the shavings in the transmission but that didn't really make sense to me.

Flushing can be risky when the history of the transmission is unknown.

A transmission flush is a maintenance process where all of the oil in a transmission is removed, new oil (and sometimes cleaning solutions) is run through it using a special machine to push out grime and sludge and then it is filled up with new oil.

If the grime and sludge is too great, the machine can dislodge enough grime and sludge to clog up the transmission.

For transmissions with a unknown history I recommend frequent Drain and Fills until one is confident the transmission does not contain excessive grime and sludge. You watch the fluid between Drain and Fills, if the fluid darkens quickly, that is a sign of excessive grime and sludge.

Flushing is a Preventive Maintenance process. Using Flushing as a Repair Process can save one a ton of money but it does come with risk as outlined above.

In Short: Flushing keeps a transmission from building up grime and sludge, but if grime and sludge are allowed to build up to excessive levels, flushing can literally choke a transmission to death.

[rp2005]

Thanks for that explanation and that makes perfect sense.

I did just get a call from the Volvo specialty shop and they said it needs a new Valve Body and quoted me at $3200. He said he would need to drop the transmission so I asked him if he thought it was possible if he could do it without dropping it and he is going to look into it. We are going to have it done though.

[mrbrian200]

Shavings in the trans.. they have no way of knowing that without opening it up. The list of codes together looks suspiciously like an electrical issue to me. Try cleaning the terminals on the electrical connector(s) that plug into the trans, check for damaged/frayed wiring, and verify proper fluid level before going any further. Multiple circuit failures could be due to water/oil/road salt intrusion into the electrical connectors past the weather seal. Salt intrusion can corrode the copper wiring. If you see any evidence of that you may need to replace pigtails/wiring.

I know Chicago well (sitting near Foster @ Sheridan as I type this) - there is no place anywhere I've ever been that is more zealous about caking the entire city in a layer of salt for half the year - so much so that I would basically expect these sorts of issues to start cropping up on any vehicle primarily driven there/here.

I'd follow this route first before letting some trans shop talk me into a new/rebuilt trans or valve body. They're not always honest: I once had a 'highly regarded' trans shop in the suburbs tell me I needed a new trans on my old Chrysler Cirrus when the code indicated on their scanner (I looked it up) was a control circuit issue most often indicating a bad MOSFET inside the TCM. $80 rebuilt TCM fixed it -- not the $2500 trans rebuild they were pressing me for. I'm pretty sure they knew what that code meant and what would actually fix it.

[rp2005]

Shavings in the trans.. they have no way of knowing that without opening it up. The list of codes together looks suspiciously like an electrical issue to me. Try cleaning the terminals on the electrical connector(s) that plug into the trans, check for damaged/frayed wiring, and verify proper fluid level before going any further. Multiple circuit failures could be due to water/oil/road salt intrusion into the electrical connectors past the weather seal. Salt intrusion can corrode the copper wiring. If you see any evidence of that you may need to replace pigtails/wiring.
I'd try this route first before letting some trans shop talk me into a new/rebuilt trans or valve body.

Thanks. They have to order the Valve Body so I am going to have the shop look into this in the meantime. Maybe they'll find something and we can defer replacing it.

[mrbrian200]

If you want another look at/verify the diag codes I have the DICE and laptop with me. If you're in the neighborhood- mentioned general locale in previous post. I'm here through Wed or Thurs but might be tracking out to the south burbs all day Tuesday.

[rp2005]

If you want another look at/verify the diag codes I have the DICE and laptop with me. If you're in the neighborhood- mentioned general locale in previous post. I'm here through Wed or Thurs but might be tracking out to the south burbs all day Tuesday.

Appreciate it! Car is at Wizard Werks right now so I would have to go over there to get access. I am definitely going to see if they will take a look at the electrical connections before actually swapping out the Valve Body and possibly go over there and ask them to show me the electrical connections. My experience with good mechanics shops is that they are happy to point stuff out on your car and show you what's wrong if you go there so I'm hoping they will do that.

[SuperHerman]

Couple items: 1) When I looked into this repair on VIDA as another forum member was having issues - VIDA does not require transmission removal to work on the transmission valve body. It can be dropped from below - at least from what I saw. If you have VIDA you can confirm.

2) The valve body swap does not sit well with me. There are two possibilities going on - bad solenoids which can just be swapped out fairly quickly or worn bores. Worn bores require either a new valve body or machining and replacing of the bores and pistons. Essentially what happens is the valve body has channels in it where transmission fluid flows - based on the direction of the flow, controlled by the solenoids which are controlled by the computer, the transmission shifts and applies power. With age the bores and/or pistons start to wear. This then causes a leak and the correct pressure cannot be produced resulting in performance issues.

To rectify this the bore is reamed out to a larger size as it needs to be straight and true. Basically a drill bit cuts out the hole slightly larger. Then a new piston is sized according to what amount of material was removed so a correct seal can be obtained. All these changes are done with standardized replacement parts. Just like what happens when an engine is rebuilt.

Unlike an engine, the valve body sometimes can be repaired with different designed pistons and seals on the pistons. This means the bores do not need to be touched. Here it depends on what is wrong and what after market repair kits are available - for your case it may not be available. But the only way to know what exactly needs to be done is by taking out the valve body and pressure testing it on the work bench. A transmission shop can do this as they have all the tools - a really good transmission shop will have the tools and reaming bits to do the job. They will also have the experience of doing a larger number of these transmissions.

A smaller shop cannot make money doing this - that is why they just replace the entire valve body. Reaming tools for your application may cost $500 - doesn't make sense to buy them if the shop does too few repairs on your transmission. So, your valve body may just need a $200 rebuild kit, but it is not cost effective for the shop to figure this out - therefore replace the entire thing.

Step it up a level - the dealer will not even touch the valve body - they just do the entire transmission. Unless the shop has trained people (cost money), special tools (cost money) and do transmission mainly (justify all the expenses) you may have to accept just an entire valve body swap.

In an ideal world - you would take your XC90 to a shop. They would hook it up to the computer and do some readings and testing. They would then have an idea what to look for and remove the valve body. They would then bench test it and confirm their diagnosis. Next they would strip the valve body down and visually confirm and look for additional problems. Then they would repair the problems either with an aftermarket kit made to address the problems without modifications other than part exchange or they would ream out the bores and replace hard parts with new ones. But, if it is too expensive to do these repairs they would replace the entire valve body. Then they would put it all back together and bench test. Then reinstall on the car and make sure all is well. You can see this process on numerous on line videos - type of transmission doesn't matter - it is the process. The basics are all the same.

All that said - it could be the case with your transmission valve body the best route and only option is to replace it. Only an experienced shop can determine this and it is case specific.

[rp2005]

Couple items: 1) When I looked into this repair on VIDA as another forum member was having issues - VIDA does not require transmission removal to work on the transmission valve body. It can be dropped from below - at least from what I saw. If you have VIDA you can confirm.

2) The valve body swap does not sit well with me. There are two possibilities going on - bad solenoids which can just be swapped out fairly quickly or worn bores. Worn bores require either a new valve body or machining and replacing of the bores and pistons. Essentially what happens is the valve body has channels in it where transmission fluid flows - based on the direction of the flow, controlled by the solenoids which are controlled by the computer, the transmission shifts and applies power. With age the bores and/or pistons start to wear. This then causes a leak and the correct pressure cannot be produced resulting in performance issues.

To rectify this the bore is reamed out to a larger size as it needs to be straight and true. Basically a drill bit cuts out the hole slightly larger. Then a new piston is sized according to what amount of material was removed so a correct seal can be obtained. All these changes are done with standardized replacement parts. Just like what happens when an engine is rebuilt.

Unlike an engine, the valve body sometimes can be repaired with different designed pistons and seals on the pistons. This means the bores do not need to be touched. Here it depends on what is wrong and what after market repair kits are available - for your case it may not be available. But the only way to know what exactly needs to be done is by taking out the valve body and pressure testing it on the work bench. A transmission shop can do this as they have all the tools - a really good transmission shop will have the tools and reaming bits to do the job. They will also have the experience of doing a larger number of these transmissions.

A smaller shop cannot make money doing this - that is why they just replace the entire valve body. Reaming tools for your application may cost $500 - doesn't make sense to buy them if the shop does too few repairs on your transmission. So, your valve body may just need a $200 rebuild kit, but it is not cost effective for the shop to figure this out - therefore replace the entire thing.

Step it up a level - the dealer will not even touch the valve body - they just do the entire transmission. Unless the shop has trained people (cost money), special tools (cost money) and do transmission mainly (justify all the expenses) you may have to accept just an entire valve body swap.

In an ideal world - you would take your XC90 to a shop. They would hook it up to the computer and do some readings and testing. They would then have an idea what to look for and remove the valve body. They would then bench test it and confirm their diagnosis. Next they would strip the valve body down and visually confirm and look for additional problems. Then they would repair the problems either with an aftermarket kit made to address the problems without modifications other than part exchange or they would ream out the bores and replace hard parts with new ones. But, if it is too expensive to do these repairs they would replace the entire valve body. Then they would put it all back together and bench test. Then reinstall on the car and make sure all is well. You can see this process on numerous on line videos - type of transmission doesn't matter - it is the process. The basics are all the same.

All that said - it could be the case with your transmission valve body the best route and only option is to replace it. Only an experienced shop can determine this and it is case specific.

Really appreciate your post. I just spent about 15 minutes trying to find a transmission repair shop in my area that I would actually feel comfortable taking my car to and came up dry. I called a few and it doesn't seem like the shops seem to have the capability of doing a Valve Body rebuild and all of them just said that I would need to bring it in before they could really tell me. Wizard Werks is currently the third place we have taken our vehicle and it is very reputable according to Google.

I just spoke with a different mechanic and he reassured me that they would test the Valve Body and look at the electrical system once they removed it and started the the repair. If they say the solenoids are bad, then I will push to see if they can just replace them. Hopefully they can do that.

All that said - it could be the case with your transmission valve body the best route and only option is to replace it. Only an experienced shop can determine this and it is case specific.

At the end of the day, I do agree with this. While getting a brand new valve body does cost a lot more, it feels like a way safer option than having a less credible shop attempt to do a rebuild. I was seeing a lot of bad reviews of shops in my area saying that they rebuilt someone's transmission and then a year later it crapped out on them.

[mrbrian200]

I was thinking the high temperature indication could be due to contact resistance in the electrical connectors. Resistance in the wiring would add to the PTC resistor/sensor giving an artificially high temperature reading. Together with the time of year (winter salt spray in the engine compartment still present + cool-damp-wet atmospheric conditions that can lead to heavy condensation under the hood when sitting longer periods such as overnight. It could well be a valve body gone bad as superherman seems to lean. I just wouldn't replace that first until you've ruled out the possibility of an external wiring issue. If the temp DTC weren't present I would probably go with the valve body straight away, which you may well end up replacing.

[rp2005]

I'm looking into some options of buying a rebuilt valve body online seeing prices in the $500s. Is this something I should stay away from? Seems like it might be a decent option if I can't find a place to rebuild one locally.