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Normal transmission temp for GXP?

Snik225

Snik225

New member
I just bought a 2007 GXP last week & I love it! One thing I've noticed, though, is that it seems to feel & smell hot all the time. No one else who has been in it with me seems too worried about this, but I am just a little concerned that it isn't normal. I have read a lot about transmission issues with these cars. Yesterday, after about 5 - 10 miles of highway driving (not hot rodding, staying around 65,) and a few miles of in town driving, about 80-something outside, the transmission temp hit 210 degrees. This seems high to me. Is it normal or should I be concerned? The main temp gauge hasn't gone much over the halfway mark. I didn't get any kind of warranty with the car, OR an owners manual (which I just ordered online today.) Any advice you all can give me as a new owner & new member of this forum would be greatly appreciated! Thanks!
 


Things to note.

LS4 block is Alluminum.

Because of that it heats up the transmission alot and cause's the higher trans temps.

The hotter the transmission the shorter the fluid life, and sometimes, it will reduce the life of the trans itself.

I tell anyone that buys a GXP to invest in a external trans cooler to help keep temps down and make it live alot longer. I strongly suggest to look into one.
 
For reference when i was cannonballing across the country (fast driving), in my 04 GTP, The trans temps got up to the high 230's.

My Regal has an external transmission cooler and even on stock thermostat i rarely see the transmission get past 200 doing the same type of driving.
 
Yikes! So since I was basically babying it, that temp is probably way high then? How often does it need flushed? This has about 60000 miles on it. Not sure if it's ever been flushed. Would that help anything? I should add, I don't put a lot of miles on cars. Only put about a few thousand a year, mostly all in town driving, (a small town, so a lot of stop and go.)
 


i changed my trans fluid as often as i can afford. ive owned my car for 14 months and changed it 5 times. it is the original trans with no rebuilds. if you sign up over at gmls4.net theres a large community of gxp people there.
 
So, I called the local performance transmission shop today and talked to the owner. He told me that anything over 200 degrees means something is wrong and would cause damage. I told him I'd been online and other owners of these cars tend to agree that they run pretty hot. I asked him about the transmission coolers, and he said, since most of my driving was in town, that I would need to have a cooler with a fan, which costs $200 or more. Does this sound right? Or would one of the others help too, do you think?

Tonight I decided to heat up the transmission and check the fluid. I drove about 15 minutes in the country, averaging about 55-75 mph, with about 10 stop signs along the way. My temperature went up to 213 degrees.

I parked it and checked the transmission fluid. It smelled burnt, and was an orangish brown color, which from the research I've done means BAD! I have no idea how long it's been this way!

Seeing as I only bought this car a week ago, I talked to the dealer I bought it from. They are going to "look at it" for me. I bought the car with no warranty, but seems to me that the transmission was bad or having problems when they sold it to me, so they SHOULD do something about it. Am I right? How worried should I be? It seems to shift fine to me so far. Although, the tires jump a bit between gears when giving it a lot of gas, but I just assumed this was from power. Maybe I am wrong. HELP?! I need advice.
 
Not sure about damage to your trans, I'm not familiar with GXP's. I do know for sure that it needs a fluid change and or flush with new filter from how you described the fluid smelling burnt and being orangish brown.
 
Thanks. I am hoping the dealership will AT LEAST do that for me without charge. You'd think they would've checked it before selling the car...
 
what happens is the trans gets hot and causes clutch pacs, and the tc to start to wear quicker than it should. these particles get into the factory trans cooler built into the radiator. this in turn causes the factory cooler to clog and makes it run even hotter. my recommendation would be this: get a hot flush done on the radiator asap. this requires removing it, but it will benifit in 2 ways. it cleans the factory cooler out and cleans any nastyness in the radiator itself from the horrible dexcool that was once in that car. next get an aftermarket trans cooler. you dont need a fan. you can run it so that the hot fluid runs into the factory cooler and then into the aftermarket cool and then into the trans. acts like a double cooler in a way. then before you even start the car after the cool install and radiator flush. change the trans fluid and filter. there is a factory auxillary trans cooler for our cars. it was an option on all cars shipped to the middle east. it is crazy expensive but uses all gm parts and is a direct bolt up.
 


Snik225 said:
Thanks. I am hoping the dealership will AT LEAST do that for me without charge. You'd think they would've checked it before selling the car...
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HAHA NOOOOO, I used to be a Jeep Tech and when I worked on trade in used cars or did UVI's (used vehicle inspection), I would write up repair/ maintenance orders and 9 times out of 10 they would reject my request to do a lot of work so they could save money. They only let me do stuff that would help keep it running long enough to sell. Then they wash it and sell it, let the new owner deal with any minor thing it might need. Not trying to scare you, but it's truth. I'm not saying most dealers are like this, but there are ones that operate like this out there.
 
Snik225 said:
Thanks. I am hoping the dealership will AT LEAST do that for me without charge. You'd think they would've checked it before selling the car...
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You'd be surprised...The dealership sold me a modded car. Modded to the point that its illegal in this state. They're just trying to flip it as soon as possible.
 
I pan drop and filer/fluid change would be a good idea.


But like you have said, taking back to where you bought aint a bad idea, seeing how they didnt look at it before they sold it to you.

As for the trans cooler with a fan, I wouldnt say you need that fan, the cooler should be enough to keep temps around 170-200.

And as for which cooler to get, Im not totally sure which one is the best. I go with what other LS4 owners have bought, take a look into it.
 
Thanks for the advice. I don't have a lot of money (cleaned out my bank account for the down payment on this car!) I live in a small town, and this is a very well-known dealership. I know A LOT of people in this town. I'm hoping that they might try to make it right, just so I don't bad mouth them out of any business. The least they can do is change the fluid and filter. It is a Ford dealership, so if they do, I hope they do it right. I've read too, that you don't want any solvents used in a flush? I'm kind of hoping they refer it over to the transmission shop. It's just down the street, and has a good reputation. The transmission shop owner just told me today that dealership sent a G8 over to him last week, because they didn't know how to work on its transmission...sigh.. Then again, they could just tell me what's wrong or say nothing is wrong, and try to send me on my way. That is why I was determined to see for myself what kind of shape the fluid was in. At least I have some ammo, and they can't play me off as the "dumb blonde." Just makes me sick that this is happening. Ugh.
 
As far as the cooler. Can anyone tell me about how much labor is involved in putting those in? The cheaper ones without the fan? I can't do it myself. I definitely want to get one as soon as I can. I've read B&M is a good brand? I will probably just order one online, and take it to my regular mechanic or that tranny shop. I just am wondering how much I'll probably get charged for labor.
 


Thanks for the detailed advice. It sounds expensive. I doubt I can get the dealership to flush the radiator, too, but I will try to suggest it, IF they offer to do anything at all to make this right.
 
Good luck with the stealership, hope they make right. If not put your foot up their starfish and don't back down. Do it tactfully, calm and stay confident. Don't just lay down. A dealer tried to walk all over my wife once let's just say after I got done with them I got results.
 
Take it in. My 05 gxp has had 3 trans's put in it. Every time I needed a new one the temp would go up over 210. On number 3 now and it stays around 180-190. Torque converter may be failing as well. Are you getting any slippage. I want to put a external cooler in but GM keeps giving me new(rebuilt) ones with no cost to me. Also, the last two I have babied and they still went. Anyway good luck.
 
Snik225 said:
Thanks for the detailed advice. It sounds expensive. I doubt I can get the dealership to flush the radiator, too, but I will try to suggest it, IF they offer to do anything at all to make this right.
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All fluids should have been changed prior to you taking ownership. They failed as a dealership and should at the LEAST do that without issue.
 
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