I just ordered a replacement 3 series carrier for my Australian 9 bolt rear end from 9bolt.com. After inspecting it, the part numbers are not only different, but the height where the ring gear sits is about 3/8" shorter than the original. My original part number is 0578-908-f-731, the one shipped by 9bolt.com is 0578-915-b-731.

My question is if this carrier assembly can be used or did I order the wrong carrier from this guy? I told Glenn the specs before I ordered the assembly from him and assured me that I could just slap it in and go. That doesn't seem to be the case yet.

Thanks in advance!

 

See if there is a way you can do a cross-reference.
Maybe go to their website & put the part #s in a search field.

Could they have sent a 2 series part? Are the 2s able to work in a 3?

I don't think a 2 works in a 3, but IDK a 2 in a 3...?...

( edit )
Posi or open diff? Used or new parts? Gear ratio?

I went to the site, lots of stuff!!
I wonder if posi & open diffs have different sizes..?..

 

Thanks for the reply back t-top havoc! The car is an 1987 Trans Am with the 373 Australian 9 bolt rear end. It is a posi diff. I couldn't find anything on his site originally so I emailed the guy and gave him my specs. He said I could either have it rebuild by a diff guy or buy his 3 series carrier. I gave him all the specs, bought it after communicating with the guy, now I feel totally ripped. I hope it is just a big misunderstanding. I rebuilt my L98 last rear and chewed up my spider gears (from wheel hop) and only put in 1000 miles into the engine. It has been almost a year since then and I am dying to get this thing back on the road. I will admit I am slightly impatient, but on the other hand a bit peeved that I spent almost $500 for something that is not what I expected it to be.

 

I didn't see anywhere a person could do thier own part # search for more info. I guess that way the people have direct contact with a tech person to answer the questions..?..

I see a series2 gears will not work with series3 carrier.

Sounds odd to be that much different in your measurement!!!

I wish I could be help, but since this is odd to me, I'll step out & see what the Gurus have to say.

I wish you luck & hope you drive soon!!

 

If the ring gear flange is about 3/8 off from your original then you got the wrong one. You need to contact them and work out a trade for the right one.

 

Thanks for the reply big gear head. What a bummer. I sent him an email and filed a dispute with PayPal. What a huge let down..

 

I just wanted to post an update. I spoke with Glenn at 9bolt.com and the mistake is totally on my end. My mechanic who tore the rear end apart said it was a 373. After reviewing the part numbers with Glenn on the ring gear, he was able to confirm that I had a 277 geared rear end, not a 373. Nice thing was that he was kind enough to assist me on the carrier info and is willing to swap carriers. What an expensive mistake on my end... Thanks everyone for the feedback!

 

So you actuall had a 2 series and the new one is a 3 series. Why not keep the 3 series differential and install a better gear ratio?

 

It would be too much of a PITA to convert it in the Australian rear end. I'd rather put in the original for now. If I decide to upgrade, I am just going to break down and get a 12 bolt 373 Strange rear end.