Transmission help

[LilRebel57]

I just completely rebuilt my s14 trans. New synchros,bearings,seals,bushings, gl-4 oil,clutch,etc. I’m still having an issue where on decel 4th gear makes a nasty grinding noise. Any help/thoughts as to what I might do?

[Kingtal0n]

Check the driveshaft end play, driveshaft joints, put a prybar on the yolk and see how much it comes out of the transmission. You might have the wrong length driveshaft or something.

I hear pretty much every SR trans has some kind of noise in 4th decel. It just usually isn't very bad, I've never heard "grinding" so much as just a long drawn out rumble. Any videos?

If you figure it out LMK because I'd like to know what causes it.

I think 4th is all the way on the end near the front of the trans. Did you by any chance measure like FSM says the snap ring thicknesses? I know its tempting to just ignore that stuff but maybe thats what causing it.

[LilRebel57]

There’s no driveshaft end play. It’s the perfect length aswell it fits perfect. I can try and get a video tomorrow and upload it.

[LilRebel57]

I found someone else’s video on YouTube showing the exact same noise I’m having an issue with. In the desc. he also says his is when he goes off throttle. https://youtu.be/JFPB66Kceds

[Kingtal0n]

yeah thats what I meant by decel. I hear it all the time in every sr trans on decel I think 4th gear.

But like I said its not really grinding (the noise I hear in all SR swapped cars pretty much to some extent).

To me, grinding is a sort of wear, like metal is being ground down. Grinded on.
If you are sure something is being worn and ground down, I would not replicate the noise any further, simply open the trans and find the worn/grinded part.

So you checked all the end play in the trans of every snap ring point? You know there are like 15 different snap rings to choose from, for like 3-4 different places, I hope, right.

http://www.freshalloy.com/showthread.php/176961-Nissan-SR20DET-Transmission-Rebuild-DIY-Thread-!

and this
http://www.freshalloy.com/showthread.php/176395-Kingtal0n-s-S14-Kouki-sr20det-Project-Repair-and-Restore?p=1627545&viewfull=1#post1627545

This is the list of snap rings and shims:
snap ring 1: $0.88/each pn: 32228-20100 (through 20103) there are 4 of them size
snap ring 2: $1.31/each pn: 32215-E9000 (through E9002) there are 3 of them size
shims for counter front bearing: $5.18/each pn: 32218-V5000 (through 5005) there are 6 of them size
Main drive gear snap rings: $2.09 ea 32204-78001 (through 78003) there are 3 different size
Mainshaft Front: $discontinued part 32263-V5200 (through 5201) there are 2 sizes different


Maybe one of these snap rings or shims is wrong if you didn't check them all.

I am looking back at it now and I think when the engine goes into a decel in 4th, because the gear is all the way on the end "main drive gear" it must have enough leverage to pull something against something. As vague as it sounds maybe try pulling the trans internals in tension with it in 4th and see what gears rub on what when you spin the shafts. If I get a chance I will try it on a spare transmissions. Maybe the countershaft is working against something, that thing didn't seem super solid in there despite it looking like a seriously important part and I've always been suspicious of it walking around whenever it feels like.

[LilRebel57]

I don’t think that’s the case. Everything in my trans fit in nice and snug. There was no play anywhere on the main or counter shafts. I literally tore everything off both of the shafts so I know it’s all fresh and new. I’m hoping maybe it just needs to be broke in a little and it’ll go away. Who knows? Lol

[Kingtal0n]

well if you can get some vids I am rlly curious if its the same noise I always hear