Author Topic: T5 Gear Questions (Read 778 times)

DEL65 · « **on:** February, 10, 2012, 08:26:08 AM »

The rebuild on my 289 should be finished soon, and I planning on replacing my T10 with a T5 at the same time. CrustyC was kind enough to give me a used T5 and I weighing the idea of rebuilding that one or not.

I have a few questions about T5's and gearing. Most of them have a 3.35 first gear. I currently run a 3.25 rear gear, but am planning to increase to a 3.55 for the 5 speed. My tires are a little taller than stock, but not by much.

I've been under the impression that T5's 3.35 1st gear may be too tall for my rear gears, and make 1st a useless 'granny gear'. I also don't think I can replace the 3.35 with a shorter 2.95 gear without replacing the entire gear package.

Are my two ass-umptions correct? Should I search for a T5 that already has the 2.95 1st gear? Thanks.

67 Fastback · « **Reply #1 on:** February, 10, 2012, 08:40:45 AM »

Not as simple as just replacing the first gear. The 2.95 is generally referred to as a z-spec ratio. To change the input shaft to the 2.95 first then you have to change the rest of the gear set to the z-spec gear set as there not interchangeable.
Bill

kb3 · « **Reply #2 on:** February, 10, 2012, 10:15:39 AM »

Quote from: DEL65 on February, 10, 2012, 08:26:08 AM

The rebuild on my 289 should be finished soon, and I planning on replacing my T10 with a T5 at the same time. CrustyC was kind enough to give me a used T5 and I weighing the idea of rebuilding that one or not.

If you decide to rebuild that T5 I have a great step by step video you can borrow to do it yourself in your garage and some of the specialty tools!

67 Fastback · « **Reply #3 on:** February, 10, 2012, 10:18:00 AM »

Quote from: kb3 on February, 10, 2012, 10:15:39 AM

If you decide to rebuild that T5 I have a great step by step video you can borrow to do it yourself in your garage and some of the specialty tools!

Can I be your friend too???

Bill

kb3 · « **Reply #4 on:** February, 10, 2012, 10:45:25 AM »

Quote from: 67 Fastback on February, 10, 2012, 10:18:00 AM

Can I be your friend too???

Bill

I am happy to loan the video to anyone that would like to use it. As for the tools, I prefer they stay close to home. Del and I live in the same town so I can go get them if I need them. As for friends....all it takes is beer!

67 Fastback · « **Reply #5 on:** February, 10, 2012, 10:46:42 AM »

I understand and appreciate the offer on the video. What are the specialty tools required for a t5 rebuild?

Bill

kb3 · « **Reply #6 on:** February, 10, 2012, 11:04:38 AM »

nothing too expensive really...some odd ball snap ring pliers, a clamp-on style dial indicator, an inch pound torque wrench....I can't remember what else. I would have to watch the video again!

66gt350 · « **Reply #7 on:** February, 10, 2012, 11:46:07 AM »

Quote from: kb3 on February, 10, 2012, 11:04:38 AM

nothing too expensive really...some odd ball snap ring pliers, a clamp-on style dial indicator, an inch pound torque wrench....I can't remember what else. I would have to watch the video again!

IIRC, that's about what we used when Sabrina rebuilt her old T-5. We didn't use a video but this service manual: T-5 service manual Warning: the manual is 2.7 Megs....

ps...I also have one for the TR-3550/original TKO if anyone is interested.

midpack · « **Reply #8 on:** February, 10, 2012, 11:49:16 AM »

I have had both T5 gear sets in my Foxbody with 3:73's in the rear. not much difference really, you go through 1st pretty quick with either one

stangg · « **Reply #9 on:** February, 10, 2012, 11:52:59 AM »

Quote from: DEL65 on February, 10, 2012, 08:26:08 AM

I have a few questions about T5's and gearing. Most of them have a 3.35 first gear. I currently run a 3.25 rear gear, but am planning to increase to a 3.55 for the 5 speed. My tires are a little taller than stock, but not by much.

I've been under the impression that T5's 3.35 1st gear may be too tall for my rear gears, and make 1st a useless 'granny gear'. I also don't think I can replace the 3.35 with a shorter 2.95 gear without replacing the entire gear package.

Are my two ass-umptions correct? Should I search for a T5 that already has the 2.95 1st gear? Thanks.

I started with a 3.35 T5 in my car with a 3.27 rear gear (8.8 rear end). The trans had an issue so I rebuilt it using the 2.95 input, cluster and 1,2,3 gears. I also replaced the reverse gear because of wear, and also added the aluminum bearing support. I think all the hard parts ran me just about $700. I think you can buy new 2.95 T5's for about a grand.

I went to 2.95 because of the higher torque capacity, and because I thought first gear was just a bit too short with the 3.27 rear gear, not useless, just short. Now with 2.95 / 3.27 combination, I do like how it drives on the street.

For what it's worth, Back in the late 80s, several grudge night drag racers where changing the rear gears on the T5 equipped Mustangs from the stock 2.73 to 3.55.

I have a shakedown video of mine rowing through the gears with the 3.35 T5 and 3.27 rear gears if you want to get an idea of what it sounds like...

David67 · « **Reply #10 on:** February, 10, 2012, 06:42:27 PM »

John,

I went to 2.95 ratio right away. I purchased the kit from Astro performance they are located in Florida. Then I had a buddy rebuild my T5 for me and he said he liked the gear set because well it was machined. There website sucks but I called they sold me over the phone. I got 400 hp kit.

I am usually all about rebuilding things myself but transmissions are still Japanese for me. Also my friend is always rebuilding T5's.

monkeystash · « **Reply #11 on:** February, 11, 2012, 05:27:27 AM »

I drove a Fox body for about 10 years with the 3.35 1st/4.10 rear combination. It was awesome. My current 2011 from the factory is 3.66/3.73. I think you'll like it.

BobV · « **Reply #12 on:** February, 11, 2012, 07:18:22 AM »

My Saleen is a 3.35 1st gear with a 3.55 rear gear. Not extra short at all. Seems "normal" to me....

On my 65, I ran a 3.25 rear gear with a 3.35 1st. No issues there either... Great take-off, and 70 mph at 2000 rpm with a 235/45/17 tire.

IMHO, IF you have to go COMPLETELY thru the T5, go ahead and swap in the 2.95 gearset. Otherwise, stick the tranny in as-is, and DRIVE the sucker!

DEL65 · « **Reply #13 on:** February, 11, 2012, 09:29:48 AM »

Thank you very much for all the replies. It's a mixed set of opinions and much to think about. A new trans is not really in my budget. It seems like my options are:

1) Keep/freshen up the trans I received from CrustyC and keep the 3.35 first gear and 3.25 rear.
2) Replace the entire gear set with 2.95's. I'll take a look at the supplier for David67's trans. Change rear gear to 3.55.
3) Look for a used/rebuilt T5 with the 2.95 gear set and add 3.55.

cmayna · « **Reply #14 on:** February, 11, 2012, 02:38:54 PM »

Shag is running a 2.95 first gear in his T5 wc and some 3.55's in his Backside. Love it.

The only thing I wished I had done differently was to put. In a .68 5th gear instead of the current .63. A little too doggy for me unless Im shifting out of 4th at maybe 3k rpm.

TapaYakin' from my iPhone

crustycurmudgeon · « **Reply #15 on:** February, 11, 2012, 07:21:22 PM »

Craig, how's the accuracy of your speedometer? I assume you have the standard 7-tooth drive gear and 21-tooth driven? I believe I have the 21-tooth driven gear and I find that the speedo is still not as accurate as it should be. They make a 23-tooth gear, but it has really thin teeth and isn't recommended.

Because of this, I think if anyone's planning on a T5 with 3.55 gears or lower (numerically higher), you should probably have a 6-tooth drive gear installed.

Frank

crustycurmudgeon · « **Reply #16 on:** February, 11, 2012, 07:32:23 PM »

Quote from: cmayna on February, 11, 2012, 02:38:54 PM

The only thing I wished I had done differently was to put. In a .68 5th gear instead of the current .63. A little too doggy for me unless Im shifting out of 4th at maybe 3k rpm.

How about a lower rear gear, like 3.70 or thereabouts?

Frank

Sluggo · « **Reply #17 on:** February, 12, 2012, 12:40:05 AM »

I'm running a stock world class T5 with a 3.00 out back. Quite happy with it.

A friend is running a 3650 (338 first) with 370s out back. First is pretty short but far from useless.

cmayna · « **Reply #18 on:** February, 12, 2012, 06:10:47 AM »

Quote from: crustycurmudgeon on February, 11, 2012, 07:32:23 PM

How about a lower rear gear, like 3.70 or thereabouts?

Frank

Frank, I don't remember if it's a 21 or 22. Speedo accuracy is very close to being dead on. Yes I considered some 3.73 gears but at this point I'm actually very happy with what I have. Not that unhappy to rip the drivetrain apart. At least right now.

B67FSTB · « **Reply #19 on:** February, 12, 2012, 10:31:20 PM »

TMBK
you have to look which driven gear your trans has by looking into the trans through the opening from the speedometercabel.The driven gear in the trans is colorcoded.
Black = 6 th
Yellow = 7 th
Green = 8 th
Combined with the rear axle ratio you can determine which gear you have to choose with this understanding that your wheel dimensions aren't changed and close to the orig dimensions are.

Otherwise ( read different/oversize tires ) see formule below this document.

http://www.fordracingparts.com/download/charts/129.pdf

B67FSTB · « **Reply #20 on:** February, 12, 2012, 10:35:52 PM »

There is a chance that you have to change the driven gear in the trans , which can be done under the car.
Follow the chart coreectly because there are combinations that are not allowed because it will ruin the teeth.

crustycurmudgeon · « **Reply #21 on:** February, 13, 2012, 01:18:27 AM »

Well, it looks like I should have a 20 tooth driven gear (works out to a little more than 19.5). Maybe I got a 19 instead. I don't know why I was thinking I had a 21. I guess I'll have to pull it out and look.

Frank

DEL65 · « **Reply #22 on:** February, 13, 2012, 07:40:09 AM »

Thanks again for all the info. I've decided to shop for a 2.95 gear package first. If I can't find anything in my budget, I use the trans Ive got (thanks again Crusty) and see how I like it.