Aftermarket Transmissions

John M · Jul 30, 2014

I dont really have any experience with aftermarket automotive transmissions, we either replaced with the same, or repaired what we had. Now a days, theres many aftermarket dealers for transmissions, some with an "upgraded" package, some a totally new design, etc. by the company selling/building them. My friend is looking at/thinking about a 6 speed (Manual) from American Powertrain for his Mustang project. My question is, as anybody ever bought an aftermarket trans, and how has it held up? He plans to use this car as a weekend driver and the occasional road trip to a car show, etc., not going to be a trailer queen.

bobs old iron · Jul 30, 2014

just depends how long they been in business,,, they can't be any worse than factory rebuilts, or another transmission rebuilder...chances are the one you buy, might already been up graded... 50/50

Chuck (CA) · Jul 30, 2014

Don't know too much, except some of them are designed to handle more horsepower than the originals. Of course you have to get the clutch/ pressure plate package to go with them. If your friend has a pretty big engine, than he'll probably enjoy it....There's also the cool factor.

Mike (WA) · Jul 30, 2014

Its probably a Tremec- pricey, but according to the reviews, worth the money, if you've got lots of horsepower. Lots of them out there, in use, and supposedly pretty bullet-proof.

John M · Jul 30, 2014

Just the factory 289, built up some.

John M · Jul 30, 2014

Had a C4 in it, but hes changing it back to a manual. (You can tell since the previuos owner just cut the old clutch pedal off, and did a poor job of cutting the floor for the shifter.) Still has some work to do to it yet before he gets a trans, but was seriously thinking about a Tremtec T6, I think is what it is, but wants to go with something aftermarket since the newer Fords that use it wont direct bolt to this 289, and hes like, if I got to spend the money to do that, I might as well spend it once and be done.

gwstang · Jul 30, 2014

There is a giant forum over at

www.vintage-mustang.com

I have a '66 and spend quite a bit of time over there.

buickanddeere · Jul 30, 2014

Summit racing has new transmissions with warrenty in 4,5&6 speed with various torque ratings .
May as well put a 351W in there or a stroker crank.

Ian Beale · Jul 30, 2014

AFIK Borg Warner manual box line got sold to Tremec

Gambles · Jul 30, 2014

Is this Mustang for the street, strip, or both?
The C4 tranny can be built to withstand 1,000 HP.

John M · Jul 30, 2014

Street mostly, probably. but the C4 is an auto, he wants to go back to a manual.

John M · Jul 30, 2014

Thanks, Ive sent him the link.

Mark - IN. · Jul 30, 2014

The automatic transmission in one of my Cummins Dodges got rebuilt by Dodge twice by the time it hit 50,000 with a 100,000 drive train warantee. It was rebuilt a third time at about 60,000 by a trans place, billable to me using non-stock parts and has over 100,000 and years on it. As I recall, the trans place is a member of ATRA, or something like that, where transmission repair shops across America that are members, will warantee.

Sometimes aftermarket is better, and sometimes not. Good luck.

Mark

Janicholson · Jul 30, 2014

I just helped a friend put a T5 (metric) 5 speed from a later mustang in his 289inch 67 mustang. We used an adapter from bell housing to trans. No real issues, it did require drilling and tapping the interface between the bell housing and adapter. It was pretty straight forward. No drive shaft cut was needed, All kit parts were correct and the shifter came out the correct location. Jim

Aftermarket Transmissions

John M

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bobs old iron

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Chuck (CA)

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Mike (WA)

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John M

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John M

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gwstang

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buickanddeere

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