transfer case - what actually fails?
10-05-2022, 01:36 PM
#106
Rennlist Member
I'm taking my 2011 958TT (25k miles) in on Friday. I initially suspected TC, but after reading through this thread I am thinking it may be PTV/diff binding.
I don't get hesitation on shifts or any surging of rpm. Just a pop pop pop sound when making tighter turns on throttle - makes no difference if car is warm or not.
Do the TC issues only occur once the fluid is hot??
Out of warranty and past the 10 year mark, so I am thinking about having the dealership replace the diff fluid, the TC fluid, and reset transmission adaptations. Any advice is appreciated.
I don't get hesitation on shifts or any surging of rpm. Just a pop pop pop sound when making tighter turns on throttle - makes no difference if car is warm or not.
Do the TC issues only occur once the fluid is hot??
Out of warranty and past the 10 year mark, so I am thinking about having the dealership replace the diff fluid, the TC fluid, and reset transmission adaptations. Any advice is appreciated.
12-16-2022, 11:17 AM
#108
Apparently the fluid is what fails, which then leads to failed hardware like the TC clutch packs, etc. I just posted the following in the transfer case sticky thread....
Yesterday I was at one of two P dealers local to me that I do business with. While checking out some new rides, my salesman introduced me to one of their more senior technicians that happened to be in the sales area at the time.
In chatting with him about a number of things, we got on the subject of the 958 transfer cases. He mentioned the latest revision of the case (which we've discussed in this thread) and the associated new hardware like the vent kit, etc.
According to him, the issue has always been a contamination of the fluid. The total amount of fluid the TC holds is very little actually (1 liter or so?), so any small amount of contamination can have significant impact, and that impact specifically degrades the friction modifiers in the fluid which is at the root of the problem. In some cases a fluid change corrects the issue (which we've seen evidence of), and then in other instances the damage caused by the fluid contamination is more severe and thus permanent, requiring a TC replacement. He mentioned that the vent kit helps reduce fluid contamination, but it is recommended now that the fluid in those transfer cases (even the new design) be replaced every 20k miles.
Just passing on this information.
Cheers all.
Yesterday I was at one of two P dealers local to me that I do business with. While checking out some new rides, my salesman introduced me to one of their more senior technicians that happened to be in the sales area at the time.
In chatting with him about a number of things, we got on the subject of the 958 transfer cases. He mentioned the latest revision of the case (which we've discussed in this thread) and the associated new hardware like the vent kit, etc.
According to him, the issue has always been a contamination of the fluid. The total amount of fluid the TC holds is very little actually (1 liter or so?), so any small amount of contamination can have significant impact, and that impact specifically degrades the friction modifiers in the fluid which is at the root of the problem. In some cases a fluid change corrects the issue (which we've seen evidence of), and then in other instances the damage caused by the fluid contamination is more severe and thus permanent, requiring a TC replacement. He mentioned that the vent kit helps reduce fluid contamination, but it is recommended now that the fluid in those transfer cases (even the new design) be replaced every 20k miles.
Just passing on this information.
Cheers all.
I'm taking my 2011 958TT (25k miles) in on Friday. I initially suspected TC, but after reading through this thread I am thinking it may be PTV/diff binding.
I don't get hesitation on shifts or any surging of rpm. Just a pop pop pop sound when making tighter turns on throttle - makes no difference if car is warm or not.
Do the TC issues only occur once the fluid is hot??
Out of warranty and past the 10 year mark, so I am thinking about having the dealership replace the diff fluid, the TC fluid, and reset transmission adaptations. Any advice is appreciated.
I don't get hesitation on shifts or any surging of rpm. Just a pop pop pop sound when making tighter turns on throttle - makes no difference if car is warm or not.
Do the TC issues only occur once the fluid is hot??
Out of warranty and past the 10 year mark, so I am thinking about having the dealership replace the diff fluid, the TC fluid, and reset transmission adaptations. Any advice is appreciated.
any update with your car?
I also have a 11 CTT and with similar issues like yours
