Mechanic bros - cv shaft broken. fault?

[aal04]

Have a car, 18k miles on it. just past warranty (6 years)

Transmission went and got it replaced. After about 100 miles, the cv shaft broke.
First reply from guy who did transmission was the cv shaft is a consumable and probably unrelated. Wants $400 to look at it. (dealing with dealership/manufacturer so prices are bloated. e.g. tranmission $12k, cooling system $10k, mechanic $200/h)

So question to mechanic/people. I know that the cv shaft is connected to transmission, but is it highly likely the mechanic didnt put the cv shaft back into transmission properly and why it broke so soon after transmission or is it possibly unrelated?

reps

[EDcellent]

How did it break? Did it snap? Bind up? Did it disconnect at one of the joints?

[aal04]

How did it break? Did it snap? Bind up? Did it disconnect at one of the joints?

It snapped yeah. broken section still in transmission.

[wasp9166]

Not hard to do yourself

Yet a pia

They don't just snap ,the boot rips ,dirty mixes with the grease and it will start making noise

Yiu can drive them quite a while b4 it fails

Def an alignment issue

It will leak fluid if not all the way into tranny

Why would a car with 18k need a tranny ?

[ClivesTriceps]

I'd be having the shop look at it. A solid splined shaft doesn't just break out of nowhere. The dude that replaced your transmission f*cked up somewhere in the installation causing it to break..

[aal04]

Not hard to do yourself

Yet a pia

They don't just snap ,the boot rips ,dirty mixes with the grease and it will start making noise

Yiu can drive them quite a while b4 it fails

Def an alignment issue

It will leak fluid if not all the way into tranny

Why would a car with 18k need a tranny ?

coolant mixed with transmssion oil. Manufacturer recommended new cooling sys (10k) + transmission (12k). Post warranty manufacturer threw in new transmission, but i have to take care of cooling system (spoke to few mechanics and decided to just do radiator and see how it goes $800 vs $10,000 for whole new system).

Drove it for less than 100miles and the cv is 2 pieces. one piece stuck in transmission.

seems like there is some critical alignment needed for transmission/cv joint and they stuffed it?

[aal04]

I'd be having the shop look at it. A solid splined shaft doesn't just break out of nowhere. The dude that replaced your transmission f*cked up somewhere in the installation causing it to break..

yeah its $600 (2x tows + 1 hr work) for them to look at it and if they dont like it i take the bill. their prices are about 3x more than bmw so dont want to deal with them unless its a lock and its their fault

[Jasonw1178]

The thing is you got 100miles on it so if it was installed wrong or broken in that time you wouldn't have made it out of the parking lot. During R&R no doubt it puts stress on it and probably pulled it out of the joint and then slipped it back in but not in the same position and it caused added stress. If it were a really good driveshaft it wouldnt' be a problem but no doubt the work on it accelerated the failure. When it comes down to it, it fall under things that happen and there isn't really anything you can do to prove it and it will cost you more to presue it in court than it is worth. As a shop foreman, what I would do is offer to replace the shaft for parts cost only, no labor since you had already been a good customer but no I can't warranty every part on the vehicle.

[aal04]

The thing is you got 100miles on it so if it was installed wrong or broken in that time you wouldn't have made it out of the parking lot. During R&R no doubt it puts stress on it and probably pulled it out of the joint and then slipped it back in but not in the same position and it caused added stress. If it were a really good driveshaft it wouldnt' be a problem but no doubt the work on it accelerated the failure. When it comes down to it, it fall under things that happen and there isn't really anything you can do to prove it and it will cost you more to presue it in court than it is worth. As a shop foreman, what I would do is offer to replace the shaft for parts cost only, no labor since you had already been a good customer but no I can't warranty every part on the vehicle.

sounds like a chit denial but thanks for your honesty from your perspective.

Im not sure if i should spend $600 to gamble their good will (considering they charge $200/h and prices are insane - I expect 3-4x typical costs for everything from this dealership). I think cv shaft should cost $1-$2k?, so i expect about $5k from them)

[KilaByte]

I really think the shop screwed up the install but how I really don't know. An axle doesn't just snap unless you're launching hard on the track with sticky tires. When it starts to fail you hear clicking when turning under power.

I'd like to know what car this is where the cooling system is 10k, my M3 has two separate loops one for the motor and one for the turbos and that would not cost me 10k to replace.

I'll fly out there for 8k and fix it for you, deal?

[headturner1]

What kind of car is this op?

[aal04]

What kind of car is this op?

I dont want to get detectived until this is resolved.

Its not a prestigious brand. Car is sub 30k brand new but is in the "reliable" non-euro category.

dealership costs for repairs are just absurd.

[i3oosted]

Does it have a rubber boot on it? Those will crack or get torn and boom. Unfortunately if it drove fine for awhile, it’s going to be hard to pin point that they caused the failure.

[aal04]

Does it have a rubber boot on it? Those will crack or get torn and boom. Unfortunately if it drove fine for awhile, it’s going to be hard to pin point that they caused the failure.

So the C clip/lock mechanism on the shaft broke inside the transmission.

[ClivesTriceps]

So the C clip/lock mechanism on the shaft broke inside the transmission.

It's been a while since I worked on a FWD drive car in a shop environment, but I don't remember there being C-clips holding CV shafts in a transaxle. You can slide them in and out and they're secured at the steering knuckle with an axle nut.

[BrahMike]

I'm confused.....

18k miles and needs new transmission already bc "coolant mixed with transmission oil"....which is not possible by the way......and now your CV shaft snapped in 2?

I wouldn't be paying for chit.....I'd also get it fixed and then immediately get rid of it.

[ClivesTriceps]

the transmission doesnt get cooled by the cooler..... that can happen with the engine oil but not transmission oil. you are either getting mixed up or they are lying to you..... probably they are lying to you because if you actually had coolant in your engine they would be talking about replacing engine gaskets.




also in general none of this chit should be happening at 18k miles...

Proof you're a f*cking idiot that doesn't know what he's talking about as usual.

Every automatic transmission vehicle has routing into a separate cooling circuit that is in the radiator to keep transmission fluid cool. Auto transmissions aren't passively cooled, you colossal f*ck-up of a human being. Auto transmission also don't use oil, they use hydraulic fluid. Only manuals use either gear oil, engine oil like some Hondas, and some even using ATF.

It is very unlikely, but POSSIBLE, to get coolant into an automatic transmission.

[wasp9166]

It's been a while since I worked on a FWD drive car in a shop environment, but I don't remember there being C-clips holding CV shafts in a transaxle. You can slide them in and out and they're secured at the steering knuckle with an axle nut.

There Are c clips

[Mang1er]

So the C clip/lock mechanism on the shaft broke inside the transmission.

How do you know the c-clip broke if the shaft is still in the transmission?

[aal04]

How do you know the c-clip broke if the shaft is still in the transmission?

shaft broke/snapped about 1/2- inch inside transmission. shaft is out, but the lil locking mechanism is still in. Mechanic says you can prolly get it out by pushing it from other side, or maybe magnet, BUT its a new transmission, and there is prolly a reason why it broke (could be alignment issues, could be transmission issue). Also 18k miles and its my wifes soccer mum car, so not as if ive got 1000hp and racing people on sand dunes.

[aal04]

It is very unlikely, but POSSIBLE, to get coolant into an automatic transmission.

spoke to 5 mechanics. all said prolly radiator/oil cooler. Replace radiator, then see how it goes. worst case need to replace cooling and transmissions

[ClivesTriceps]

spoke to 5 mechanics. all said prolly radiator/oil cooler. Replace radiator, then see how it goes. worst case need to replace cooling and transmissions

Automatic tansmissions are very sensitive to pressure changes and fluid breakdown. If you lose pressure for even a second, you will burn clutch packs up. Fluid breakdown, or contamination in this case, will can cause similar damage.