Help 05 GXP tranny not engaging

[EJT's GXP]

I was driving my 05 GXP with 98,000 miles on it yesterday and something very strange happened. It started up in the morning and I drove to my office like a million times before. I had to run out to pick something up and it drove to the store great. When I got back in after 10 minutes in the store the car would not move. I could shift into all gears, but the transmission would not engage, it was in neutral.

There was no strange noises or burnt smell coming from the car on my way to the store, it just gave up.

I had it towed to the dealer and he is saying I need a complete new trans $5500.00. They said they droped the pan and there was metal shavings in the fluid and no pressure in the unit. Is this possible with no warning at all??


HELP!!

Eric

[EJT's GXP]

Additional information:

i just looked up my service records and I replaced the fluid on 11-8-07 @48,242 miles with dextron 3 at a dealer.

[00Beast]

It's definitely possible. Look on www.car-part.com for a used one, and maybe talk to a tranny shop and see what they say. Dealers are known for way over-charging.

[harofreak00]

$5500 mean you need to find a new trans shop.

[EJT's GXP]

Thanks for the reply. In reading older posts you seem very knowledgable on this car, but that is not the news I was hoping for. My experience with tranny replacment is to go with NOS with a warrentee over a refurb.

The next question is should I fix it or try to sell it as is. on a scale of 1-10 my car is a 6.5-7 (average). It is bone stock and my daily driver. Before the tranny issue I estimated a value of around $8000.00.

I am going to pull the car from the dealer and get another estimate on a replacement.

[harofreak00]

All depends on how much you like the car. If you are ready for something else, just drop in a good low mile used tranny (probably under $1k) and sell it immediately. If you want to drive it for a lot longer, get a full rebuild (around $2500) and drive it into the ground.

Where are you located?

[00Beast]

No one is going to want it with a bad trans. You'll have to get the trans fixed to get it to sell, and you will never re-coup your cost. Get the trans fixed and it'll last you a long time. I had Aamco rebuild my trans (family friend did the job) and it's been great for a year and a half and 20k, and I don't drive easy. Get a lifetime warranty on whatever you end up doing.

[EJT's GXP]

I am in the Detroit Area. What could have caused this sort of instant failure in the trans?

[00Beast]

It's really hard to tell until you tear into the trans. It could be any number of things.

[CMNTMXR57]

Whoa, let's back the horse and apple cart up here folks! Were there any codes being generated?

There could be a number of things wrong that don't even touch any of the actual transmission internals that have to be exhausted first. 9 times out of 10, you'll find the problem and stave off actually needing a new transmission.

O.P., did you check the fluid level? If so, what color was it? This is a tell tale sign of converter wear if it's burnt color.

Where I would focus my efforts on (especially if your fluid color is a dark, dark red) and their diagnosis of no line pressure... Torque Converter;
- low/no fluid
- Broken lug, sheared lug bolts, or failed welds
- Worn turbine shaft splines
- Pump hub damaged
- Broken pump shaft
- internal failure
- worn clutches

While yes, something like this will still be a costlier repair than a simple oil change or something, simply as the trans will have to be removed. But a new torque converter is a sh*tload of a lot cheaper than a whole new transmission.

I would seriously get it to a reputable transmission capable shop (or dealership you trust) and get an accurate diagnosis.

[EJT's GXP]

I just returned from the dealer and they did not try to pull any codes. They said they checked the pressure and it came up zero in three gears. This lead them to the complete failer diagnosis. They quoted me Est. $4700.00. $2500.00 for the part and 20 hours labor+fluid and misc.

I am pulling the car today to a guy i trust that will give me an honest assesment. I am not ready to through the dealership under the bus yet, and will keep everyone up to date on what i find out. SHould be interesting.

[CMNTMXR57]

Yea, that zero pressure could be a number of things I posted above. Pump hub damaged, broken pump shaft, etc. Those won't (or shouldn't) necessitate an entire trans though.

So yea, that second opinion from the guy you trust will definetely put your mind at ease.

[00Beast]

Any Updates?

[EJT's GXP]

Sorry for the delay guys, I just returned from vacation and picked up my car. My guy droped the trans and replaced the torque converter and trans axle assy. He had 15 hours labor and $343.50 in parts for a total of $1782.11 including the tow. The car runs great, I am so glad I pulled it from the dealer.

Thanks for all the advice!

[Bigerik]

Sorry for the delay guys, I just returned from vacation and picked up my car. My guy droped the trans and replaced the torque converter and trans axle assy. He had 15 hours labor and $343.50 in parts for a total of $1782.11 including the tow. The car runs great, I am so glad I pulled it from the dealer.

Thanks for all the advice!

Were the rest of the guts good enough to not to do a full rebuild on it while it was out?

Transmissions seem to be going frequently around here. Almost makes me wonder if I should do a pre-emptive rebuild on mine!

[RJolly87]

No need for a preemptive build, just save up for when it does blow. Then you will have that much more money for that much better of a build

And trannys were never a strong suit in these cars. I knew that going into it, but they are not by any means a weakness. Just happen to be the weakest point. I know that mine can die at any time, but is doing quite well right now.

[00Beast]

The 4T80E is quite a stout piece though. Guys with turbo STS's and the like run them with 900+ ft-lbs stock.

[CMNTMXR57]

Sorry for the delay guys, I just returned from vacation and picked up my car. My guy droped the trans and replaced the torque converter and trans axle assy. He had 15 hours labor and $343.50 in parts for a total of $1782.11 including the tow. The car runs great, I am so glad I pulled it from the dealer.

Thanks for all the advice!

Good thing I chimed in! Otherwise you'd be out a couple thousand and have a whole new trans in the car!

[CMNTMXR57]

The 4T80E is quite a stout piece though. Guys with turbo STS's and the like run them with 900+ ft-lbs stock.

On a T80E or an L80/85E? The newer STS is a RWD car, and now that I think about it, is a 6L80/85E.

I would be worried about our halfshafts before the trans personally. Keep in mind, the torque converter can absorb a lot of the "shock" to the trans from a sudden surge of power, so tuning the clutch slippage/engagement, as well as keeping torque management settings in check is what is keeping those trans alive. Also progressive levels of boost add helps save things too.

Run all balls out with a high stall, high line pressure, and no TM, and nothing GM Hydramatic makes is gonna survive 900 ft/lbs of input shaft torque.

I know this is comparing apples to oranges, but I just had my Tremec T56 built to handle 750HP/700 ft/lbs of torque, and it from the factory is more stout than any 4T80E and it's a manual (meaning no valve bodies, hydrualics, solenoids, etc). So there is no way, a stock one will last long against 900 ft/lbs of torque.

[Bigerik]

Continuing on the tranny rebuild thought (not for me right now, just in general), is there anything that should or could be done to a 4T80 to improve it? Higher stall convertors? Better or stronger internal parts? Any mods?