The bearings in my original tranmission (140K miles) were finally going out so I knew I needed to replace it. I could get a new one from MazdaComp for about $2100 or get my original rebuilt for about the same price.

Instead I bought a used J-Spec transmission from a guy named Brian in Los Angeles for $550. Brian is a school teacher but each summer he goes to japan and fills it with low mileage FC and FD powertrains. He sells the engines pretty fast but has tons (about 40) of FD transmissions in his storage building. The one I bought had only 30,000 KILOMETERS on it. I installed it the next day and it performs like a brand new transmission. I'm very happy.

If you'd like to contact him his e-mail is: ss427bb@hotmail.com

-John Magnuson

 

haha, it cost me about 350$ just to do my 5th syncro job.

 

Good deal! I think the only downside would be the Japanese trannies I THINK have a shorter 5th gear ratio. That would have you cruising at a higher RPM in 5th and bring the top speed down some. Dunno if it would be troublesome enough to worry about.

I've thought about doing the same thing if my tranny went south .

Thanks for the info!

Dale

 

^This looks good, except for the even SHITTIER fuel mileage you'll get if this is true lol.

 

Depends on how steep the JDM 5th gear is. I think the difference in 5th gear cruising would be pretty small, fuel economy wise.

Of course, you could always swap in the US 5th gear .

Dale

 

This is VERY interesting. My understanding was that the tranmissions were exactly the same.

HOWEVER... I have noticed that the RPMS are ever so slightly higher in 5th gear. It was slight enough that I really thought it was just me until I read this post.

Fortunately this does not bother me at all. I'm not too worried about freeway cruising RPMS and I always felt the 5th gear was too high anyway!

-John

 

Yeah, if it's just a minor difference in RPM's, it's no biggie. If it's like a HUGE difference, it would suck .

Dale

 

It is pretty minor... I think... I'll have to pay close attention when I drive tonight. Does anyone know the exact ratio difference between the Jspec and US 5th gear?

I think I remember it was spinning at more like 3500pms at 90mph rather than around 3200rpms or so at 90 before... does this sound right?

I'm actually happy to have a lower 5th gear. I do some road racing and while most tracks don't need 5th gear the US spec 5th gear hardly pulls when you need it.

 

found this from an old post regarding 5th gear

.719 (US)
.762
.806

 

any idea which of the latter two ratios is for the JSpec transmission (1995)?

 

The 5th gear is on the back of the trans and can be swapped without tearing down the entire trans.

 

Anyone know of a place that sells a specialized gear for the Fd tranny? When I get finished with my 20b swap, I want to take advantage of my 20b's low end torque and run a taller 5th gear for cruising. I think the stock 5th gear is like .76. I'm looking for something like .50-.60 for a 5th gear ratio.

 

T-von that is a sweet idea, swap them out for even BETTER furl econo, wait a second, if we own high end sports should we not be able to buy gas for them??



well when i get mine (early 2007 cause of importation laws) i'll be up to selling that extra 5th gear if anyone wants it. cause i like conversing fuel, the government gets enough of my money already. i say good idea go for it and us 5 just for cruising .


Prôdigy

 

Thanks for this heads up!!

 

i'll make sure to shoot you a PM in 2007.

 

has anyone else ordered a transmission from this guy? I'm considering buying one curious as to the quality, he told me he inspects them all an never had a bad one. I just resently did a full rebuild on my tranny as in finished last friday and the car is already down due to the transmission being locked in 4th gear. :|