Transmission Opinion

Mfox89

Member
Sep 20, 2016
20
1
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Georgia
New member here..need opinions on a good transmission that would be great with my 400rwhp 89 gt..I currently have stock t5 and synchros starting to fail..rather replace than rebuild, thanks.
 
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A Tremec 3550/TKO/TKO 500/TKO 600 is a completely different transmission from a T5. Strong and almost bulletproof unless you run them without proper lubricant or full throttle shift without the clutch.

A Tremec T5 is still the same T5 that is prone to self destruction when used in a street/strip or racing environment

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T5, all versions used in 5.0 Mustangs

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Tremec 3550/TKO /TKO500/TKO600 AFTERMARKET replacement for T5 - handles racing environments with ease
NOTE: the 3550,TKO, TKO500 &yTKO600 use a different bellhousing from the T5. The TKO, TKO500 & TKO600 use a different 26 spline, 10.5 clutch disk. They also use a different driveshaft yoke, which normally comes with the transmission.

See http://www.ttcautomotive.com/English/products/tremec.asp for more information - check out the "Light Duty" group, since TTC makes monster transmissions for big trucks as well as passenger cars.


T5 identifier information.

On the tail shaft of the transmission, there will be a stamped aluminum tag. The tag will have a number on it that you can cross reference to the chart below. There is no other way to find out what type of T5 it is without disassembling it. All the rest of the numbers on the outside of the T5 case are part numbers which are not unique to any particular T5 model.

Remember that 94 - 97 T5's have a longer input shaft (about 11/16” longer) and can only be used with a 94-95 bell housing unless you modify or replace the input shaft.

T5's used with a 4 cylinder have a 3.93 first gear, reduced torque ratings and an input shaft pilot diameter that is smaller that the T5 used for V6 & V8 engines. The pilot diameter is .59" compared to the .668" used on V6 & V8 T5's. It requires a different pilot bearing to be used with a V6 or V8. The pilot bearing you need is for a Ford Ranger diesel from AutoZone part #14672


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I don't know how you feel about the DYI thing when it comes to gears, some people don't like the idea of working on transmissions. If the DYI transmission fix idea isn't something that you would rather leave to someone else, here are some resources:

See http://www.ttcautomotive.com/English/onlineorder/product.asp to download a FREE service manual for T5 or Tremec 3550/TKO
You will need the Adobe Acrobat viewer which is also a free download – http://get.adobe.com/reader/

See http://www.hanlonmotorsports.com/ or http://www.ddperformance.com for parts

A T5 rebuild kit with syncros, bearings and other small parts costs about $160. It does not include any gears or shafts.

http://www.hanlonmotorsports.com/ also has a video on how to rebuild your T5 or Tremec. It costs about $20, and is worth every penny of it.

I did a Tremec 3550 rebuild, and it wasn't that difficult. The video was an immense help, and I would recommend viewing it. At $20, it will give you an opportunity to look and decide for yourself if you think that it is something you want to try to do.


T5 Shim kits – best product I have seen in a while… http://www.5speeds.com/t5/shims.html
“The Peel ‘n Place T5 World Class shim kit makes shimming T5 counter gear and main drive gears very easy.”
 
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not sure what your budget is, but the Astro A5 fully gussied up is a real slick working unit.
Shifts smoother than the stock T5.
You will need a new clutch with it... 26spln (IIRC)
 
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Jrichker, is there anyway to upgrade these T5s. For someone who may not be able to afford 3550,TKO 500 or 600.

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There are all sorts of upgrades, but unless you are a careful buyer and a skilled mechanic, they are not any cheaper that buying a 3550,TKO 500 or 600.

You end up buying a kit, and then assembling the transmission. If you have done this sort of thing before or have all the tools and mechanical skills, it can be done. There are free manuals and a $20 video that shows how to overhaul either a T5 or a 3550,TKO 500 or 600. See the links in my previous post.


Check eBay for a used 3550,TKO 500 or 600 with some sort of warranty. You might find someone parting out a wrecked car and find something that fits your budget.
 
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The 3550/tko options above are going to be the cheapest and most reliable 5 speed upgrade to take the abuse of 400 hp. If you go that route, be aware that they come with a few different gear ratios. The main difference is first gear and fifth gear. Also be aware that some guys will mod these and remove fifth gear completely.

As far as the effort to upgrade, it's actually pretty easy. I went from a t5 to a tko500 years ago in my parent's garage using basic hand tools and had almost no knowledge of what I was doing.

You essentially jack up the car, and pull your exhaust out of the way.
Remove the drive shaft with a couple bolts. From inside the car, remove the shifter boot and the shifter. Support the trans with a floor jack. Remove the bolts in the crossmember. Remove the bolts on the bell housing connecting to the motor. Disconnect the clutch fork. Then pull it all out.

For reassembly, you should be able to use the stock crossmember, but you'll need a new transmission mount. The bolts will align further to the rear of the crossmember, but there should be enough room for adjustment. You can also reuse your entire clutch cable setup (cable, pedals, quadrant) from the T5, and I believe your flywheel also (someone else should confirm, been a decade since I've swapped). You should get the flywheel resurfaced by a machine shop if reused. Won't cost much at all.

You will need a new bell housing, shifter, clutch, driveshaft.

If you have all the parts and tools, you should be able to do the entire swap in the garage in a day. Maybe two of you take a lot of beer/football breaks like I do.

If you are patient, you should be able to get all the parts you need, lightly used, for between 1,200 and 1,600. Easily can do this used for under 2k if you shop around. If you go all new, this swap will cost you much more... In the 3k-4K range.
 
I'd put the money into a tko or t56.
Heavily worked gforce or astro's cost just as much (sometimes more) than tko's.

IMO, the choice is easy, the tko's are built from the ground up to be strong, strong internals on the other two are still installed in an inferior case.
 
If sticking with a T5 platform, Astro is the best. I am currently rebuilding my Gforce T5, which was the best T5 upgrade option years ago, until Astro came on the scene. It will probably be after Christmas before I am done, but I am thinking about selling it and going auto.

Just as a reference point for you, my unit will be fully rebuilt with new bearings, seals, synchros, new sliders and two gears replaced. I am hoping to get $1500 for it. That will be my bottom dollar. Considering a new T5 is $1600-$1700 now, I think that is a pretty good deal for someone. It would cost $2k or more to build it.

Good luck with your decision.

Joe
 
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I'd put the money into a tko or t56.
Heavily worked gforce or astro's cost just as much (sometimes more) than tko's.

IMO, the choice is easy, the tko's are built from the ground up to be strong, strong internals on the other two are still installed in an inferior case.
Just talking here, not trying to argue, as there are options for folks and that is a great thing about our Fox bodies.
TKO's require a new shifter, bellhousing and driveshaft... ?? I'm not sure but I think that's the case. This all adds up making the cost... ???
Then, to make TKO's work without blocked shifts in a near all out situation, you need address items inside... or "granny" shift.
Even then, just driving, they are notchy... not butter like a T5 or the even better Astro.
Still again, TKO's are not as efficient as a T5 variant, and rob more hp. Of course at some point the 2-3% robbed power is meaningless if the trans is not going to stay together.
If you check all the option boxes, the case is no longer an issue under ~550hp. It's the mainshaft flexing that causes the case to be problematic... not the case itself.
Having said all that, yes, a full zoot Astro is not a budget build.

With -450 at the wheels on slicks, "I" think the Astro is an option to consider heavily... over that, not so comfortable. I would run one up to the rated 600hp if it was never going to see slicks and VHT.
 
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What's the cost to build an astro transmission to hold 450 horsepower

Base kit is around $1500 bucks I believe. If you need new bearings and synchros, plan on a rebuild kit too. Pressing bearings on and off is going to ruin a few of them. You are talking a realistic build cost, DIY, of approaching $2k. You can probably keep it a little south of there. The mainshaft upgrade is almost $500 more, then a case upgrade is about $350 more. But like stated above, they shift great.

My Gforce is rated to 450lbs of torque since it uses the stock mainshaft and not the upgraded one. I will be in my rebuild almost $1k by the time I am done, mainly due to the gears needing to be replaced. But it is 10 years old wit lots of miles and passes on it.

Joe
 
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I've never had any shifting issues with my tko, my car puts down 480rwhp and 500rwtq.
My engine goes mid high 6000's, never misses a gear.
I don't consider it notchy, but it's been probably been 10 years since I drove anything with with a t5.
I got a deal on my trans new with the Bell housing, adjustable cable, clutch, shifter, $2000, but even if I had to pay retail, i'd still do it again.
 
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My experience with the tko (keep in mind this was 10 years ago, and are newer tko models I have no experience with... The tko was definitely more notchy than the T-5. I ran a Steeda Tri-Ax shifter on each. I know adding that shifter made the T5 more notchy than stock, but the TKO was far more notchy.

But to each his own. It never bothered me for daily driving or at the track.