New to this forum, but it looks great. Not sure if I should post this here or in GEN 1 area.
I’m original owner of ‘79 manual and new owner of 79 automatic. Manual vehicle hasn’t been driven in 30 years and I just had a shop remove the tranny and put it into the “newer” (23K miles) 79 that had an automatic. A transmission shop inspected the manual transmission and gears. All looked good and it shifted properly.Just took the transplanted car out and it does shift fine, but there is a distinctive whirring sound in first, second, third and fifth gear. Fourth is quiet and normal sounding. Sound only comes during acceleration and not when coasting or downshifting. These sounds were not present when the donor car was last driven 30 years ago.Would love to hear opinions on what’s happening.Thanks!

 

check the rear end fluid?
might be pinion related.

I would think the gearing between the 2 trannys might be different, but others would know better.

 

would that still make sense if 4th gear works quietly?

 

I don't want to send you down a rabbit hole...but the pinion will whine when decelerating when to loose. whine when accelerating when it is too tight. thats why I said maybe the fluid.

but yeah...it whines under load...1,2 & 3 have more load than 4...and if you get into 5th and are at low rpm it is also under a lot of load. usually 4th is around town and not much load.

could be whateve fluid they used in the tranny too. I would look there 1st or at least find out what they put in it.

 

Thanks for the quick reply. Really appreciate it!What type of tranny fluid should they have used?

 

welcome to the board.

https://www.rx7club.com/1st-generati...ou-use-937254/

another thought on the whining issue ... maybe the input shaft and/or it's bearing.

and just out of sheer curiosity, what happened to the original '79? why did you take the tranny out of it?

 

Thanks for suggestion. If shaft or bearing, wouldn’t I hear it in 4th, too?
My original ‘79 was too rusted out to refurbish. Bought same year and color, but automatic and not nearly as fun to drive.

 

i can't think of a coherent argument for why that would be. i was merely putting something out there in case other suggestions (whatever they may be) don't pan out for you.

you said the car didn't move for 30 years, and a shop took it and did the swap for you. any number of things could have gone wrong because of those factors alone.

actually, another thing i thought about while typing is this car was automatic, which i think means it did not come with a pilot bearing. do you have evidence that the shop installed one?

 

This also means they had to install a clutch mast and slave cylinders, flywheel, clutch disc, pressure plate, through out bearing, clutch pedal, manual brake pedal, and pilot bearing seal. I hope they also replaced the trans gear oil.

 

I’ll check on that- thanks.