Zedman

Hi Klaus-I have a really nice '81 Avanti II with a 305 V8 and TH350C transmission (with lockup TC) with only 67,000 original miles (but rotted out Frame and non existent HT's !). It has been untouched since new and largely laid up for 17 years before I bought it and imported it into Australia. Like yourself, I felt that I should rebuild and renew knowing what old transmission seals look like given time (I have a Blog here... http://studebakerflightomatic.blogspot.com ). The engine had a worn out camshaft and I really didn't need to rebuild the whole thing but I did. I completely disassembled the TH350 and rebuilt it (even paid for a dyno test to make sure I hadn't buggered it up). I learned an awful lot about this Transmission the hard way and now have the benefit of knowledge. However... as I started to go through the parts, I found that despite its age, it was absolutely perfectly serviceable and was a waste of time. Oh yes , I did find the lockup solenoid faulty and the Speedometer drive will need to be re sealed, but the rest- perfect, Friction Discs/Clutch Plates perfect, with nice soft O rings everywhere. I know I seem to contradict myself, but if your tranny is going to cost you big dough, if it is functional, maybe leave a sleeping dog lie and spend it elsewhere? Best of luck- you are gunna love that car !

I started this thread so I'd better reply- Thanks Lew, much appreciated. I found I had to delete the photos from my various posts. Thanks for the additional space BTW.

Egbert, as a former Marine, strikes me as the sort of man that wouldn't want to be seen as being a 'crybaby' by ordering that employee dismissed. I know nothing of his personality in actual fact- he just looks to me like a real no nonsense type of fellow.... Out of interest, does anybody have any inside info on how Sherwood Egbert rolled?

Whilst I'm no expert on this subject, research into my TH350C led me across a number of sites... I believe you may need a device to substitute for the Computer Controlled Shifts/Torque Converter lockups with either of these transmissions. I have recollections of the 200r4 being a more convenient swap, and the 700R being able to take more abuse. Food for thought.

Hi Quicksilver- Interesting you say you have a 305 cid in there for that vintage of car. BTW What transmission do you already have? My slant on this is to ask a question about two things.... how much do you want to spend and is horsepower an issue... If it's a horsepower issue, by all means follow the suggestions you've been given by the knowledgeable souls so far (up engine, OD transmissions, EFI etc). I also promote the KISS principle- I'd wonder whether just rebuilding what you already have would be the route best travelled. I have just rebuilt my 305 SBC and also the TH350C (lockup torque converter trans) - it has cost me very little and is DONE. I even had the transmission test run on a dynomometer to check its operation after I rebuilt it. Thing is you ought to drive this Avanti- not spend a lifetime working on it Just my humble opinion, mind... 🫡

Thanks Wayne- Looks like I need to spend a bit more time poking about my project. Yes, I've seen it but maybe I oughta be more diligent reading it, especially where it sez... Except for access to the rear support feet, all work is done from the outside of the car- removal of the headliner is not necessary.

Geoff , whenever you tackle this job, would you mind posting a few pics so we can see what things look like behind all the coverings- everything helps.

Hi Ronmanfredi- Thanks heaps for your advice and the photo. This will be a great help moving forward. My Frame is, thankfully, still attached to the roof. Sounds like the difficulty moving the Blind is the result of muck jamming it all up.

I have had to replace my 1981 Avanti II's rear brake cylinders with genuine new ones- these are 13/16" bore units very inexpensively from a Mustang parts supplier for 1967-69 models. They are a Dorman product. I started a thread on the AOAI site addressing this a few months ago. Sleeving to original bore is of merit, but do consider costs involved (it's reached poisonous prices here in Oz!) Appropos the Proportioning valve- good idea. I decided to replace the obscure Kelsey-Hayes unit in my '82 with a GM style 'PV2' all Brass unit meant for Disc-Drum brake combination. you can mount this high up next to your booster or down low on the Frame Rail. I have various Pics- if you want these PM me please.

Hi Ronmafredi- Much appreciated. Thank you for the detailed procedure to remove the Glass Panel- that will help. I assume the "Headliner Panel" is the Sliding portion and it's removal isn't problematical... mine is pretty well stuck. Because I have pulled out some wisps of very corroded mild steel, I daresay some surgery is required to rectify the innards. I hope I will have enough space to do this without major removal of roof lining et-al.

Thanks MFG- not quite what I expected but wilco on that....

If there is anybody out there that provide any guidance / advice om removing a headliner (on an '1981 model or thereabouts) and / or getting at the bulk of the 'Moonroof' , I'd really like to hear from you. My Moonroof . I feel that I need to dive into investigating the Moonroof Before I get involved with repainting the body in 2025. I've already fished out some rusted sheetmetal from up there and know that I'm in for heartache if i don't investigate it now. whehter I repair it or delete it- only investigation will determine that path. The sliding panel in the ceiling is stuck and had to be pushed back forcefully just to gain a small opening, so far.

There is a lot of meat in the 13/16" bores- It struck me that they could be drilled & reamed out to 7/8" and a new kit of parts put in...?

Yep solved it- thanks for the offer Bill; waaay cheaper to replace the cyls with the units the Mustang parts sellers have..

Be aware that many SBC's around late 1970's through to early 1980's had problems with cam and lifter wear (particularly giving 305 cid haters more justification to vent). My Avanti II's 305 (1981 year) showed horrific wear on three lobes and 80% of the lifters utterly destroyed- and only 65,000 original miles ! How it ever ran, I don't know. If you're not intending to rebuild a second hand engine, at least look at the Lifters and Camshaft, Timing Gears and Chain. You ought to look at an Automatic overdrive transmission swap while the opportunity presents, unless of course you'd like a 4 or 5 speed manual...