s14 diff bolts to subframe free spinning - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

SuperDK · 03-23-2021, 02:48 PM

Not sure how I fucked up so badly, but now the bolts that connect the front of the diff to the subframe are free spinning so I can't remove them. I'd rather not remove the subframe. I'm trying to grind off the head of the bolts to drop the diff then see what's up from there. If the threads or nut in the subframe is salvageable or not. idk. anyone got experience with this?

SuperDK · 03-23-2021, 02:53 PM

https://imgur.com/gallery/ggTqqZ0

e30gangsta · 03-23-2021, 07:58 PM

You stripped it. Diff has to come down and you either have to helicoil, or step up to the next bolt size.

Rustys14 · 03-23-2021, 09:52 PM

This happened to me years ago when I had my old s14. The nuts inside the subframe are only lightly tacked on from the factory and seem to be prone to breaking due to age/rust. Based on the pic it looks like you have an s13 diff in your car so someone likely crosthreaded the bolts when they installed it and the removal force was more than the weld on the nut inside the subframe could take.

This isn't what you want to hear, but if the nut is spinning there really isn't a good way to fix it without dropping the subframe. If you can find a good way to pry down super hard on the front of the diff, the force may be enough to keep the nut from spinning while you remove the bolt if your lucky. What I did with mine was drop the subframe, cut access ports above the nuts and weld new ones in place. It really isn't a ton of work if you have the tools, but I'm getting old and lazy so if it happened to me again I would probably just source a new subframe and call it a day.

SuperDK · 03-29-2021, 06:33 PM

Yeah I guess my next plan is to drop the subframe, cut access holes, and put new nuts. Sucks lol

SuperDK · 04-08-2021, 04:14 PM

Ended up drilling a 1 3/8 hole with a hole saw bit. got new hardware from home depot and blue locktite to hold the diff securely. It's easier for me to get the diff out by dropping the subframe, so it's not too big of a deal. sucks but issok for now.

https://imgur.com/gallery/lG4PVCR

03-23-2021, 02:48 PM	#1
SuperDK Join Date: Aug 2015 Location: San Diego Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	s14 diff bolts to subframe free spinning Not sure how I fucked up so badly, but now the bolts that connect the front of the diff to the subframe are free spinning so I can't remove them. I'd rather not remove the subframe. I'm trying to grind off the head of the bolts to drop the diff then see what's up from there. If the threads or nut in the subframe is salvageable or not. idk. anyone got experience with this?

03-23-2021, 07:58 PM	#3
e30gangsta Zilvia Addict Join Date: Oct 2013 Location: Denver Colorado Age: 39 Posts: 613 Trader Rating: (4) Feedback Score: 4 reviews	You stripped it. Diff has to come down and you either have to helicoil, or step up to the next bolt size. __________________ Need aftermarket parts? PM or DM me competitive pricing! IG@S13Guille

03-23-2021, 02:53 PM	#2
SuperDK Join Date: Aug 2015 Location: San Diego Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	https://imgur.com/gallery/ggTqqZ0

03-29-2021, 06:33 PM	#5
SuperDK Join Date: Aug 2015 Location: San Diego Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	Yeah I guess my next plan is to drop the subframe, cut access holes, and put new nuts. Sucks lol

04-08-2021, 04:14 PM	#6
SuperDK Join Date: Aug 2015 Location: San Diego Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	Ended up drilling a 1 3/8 hole with a hole saw bit. got new hardware from home depot and blue locktite to hold the diff securely. It's easier for me to get the diff out by dropping the subframe, so it's not too big of a deal. sucks but issok for now. https://imgur.com/gallery/lG4PVCR