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I'm trying to plan ahead....

I'll have a stockish/mildly built 261. (The good 235 head, milled-not sure how much yet, dual exhaust, single carb, probably stock cam)

T5.
No id tag on the s.o.b. (I'll know what gears this weekend)

I'd like to cruise with traffic, but be capable of the occasional burnout. Emphasis on the cruising.

I realize I've left some variables WIDE open, but can anyone provide what gear ratio I should be looking for? ie: "My T5 has "X" gears, and I run 3.73:1 third member and do that with my stock 235"
That sort of advice....
I figured if I got enough input, I'd be able to make the best decision, once all my variables are known.

The truck is a 49 3600.
Absolutely no working for it, just looking good, and burning gas is all it's going to do.

Are you going to change the rearend? I know from our previous conversations that you are planning to stay 8 lug.

You're rearend is more than likely a 4.57 HO52, so you may be lucky to find 4.10's for it. Otherwise, you have to swap out to a 14 bolt, Dana 60 or some other rearend.

I REALLY want to stay 8 lug as my tires and wheels are almost new. That being said, I've come to the conclusion that because my drums are no longer available, I'll be looking into a rear end swap.

An 8 lug 14 bolt full floater out of a cab & chassis 1 ton is an almost direct bolt-in. If you can find one with a gear ratio somewhere in the 3.70:1 range, you should be able to smoke a tire occasionally and still keep up with traffic. If you use a non-locking differential, lighting up one tire won't be a problem at all. The T-5 won't like it, however- - - -it's not torque-friendly and if you encounter a sticky spot with good traction during your burnout you'll be sending the transmission to the dentist to get some tooth implants!
Jerry

"Full floater"- - - -the kind with the big center hub and axle shafts that don't carry the weight of the vehicle- - -like the HO 52 you're running now. "Semi-floater" rear axles have an axle flange that the wheel bolts onto and which also carries the weight of one corner of the vehicle on a single bearing. Either type can have eight lugs, but the full-floating axle with two bearings in the hub is more traditional.

"Cab and Chassis"- - - -a vehicle sold by a manufacturer with only a cab, front end, and a bare frame for aftermarket companies to equip with a cargo box or other dedicated commercial body. Some of them have the front section of a van installed with a big hole behind the driver and passenger seat area.

"Non locking differential" - - - -not a posi-traction.
Jerry

What's a full floater? Also, I'm not familiar with "a cab and chassis 1 ton".... can you please dum it down fer me?
As for the T5... I'm not talking about full on, car show, tire melting burnouts, just an occasional extended chirp for my son, or the neighbors. Think it could handle that?

Thanks Jerry.
How about the T5? Do you think it'll hold up to the occasional light abuse, or is it really that weak? Is there another 5 speed as easily swapped in that is stronger?
You also mentioned that the 1 ton axle is almost a direct bolt in... what will it take?

This is what a 14 bolt swap takes.
https://www.stovebolt.com/ubbthread.../14-bolt-axle-swap-info.html#Post1249600

Another larger 5 speed Overdrive that can be made to fit, but more expensive and little more work, is the NV4500. Some searching the forum may explain that process.

It’s very likely that you could use modern drum brakes from a 14 bolt on your original Eaton, as yet another option. I haven’t researched this enough to know just what’s required, but I’d bet it’s possible and not terribly difficult.

Grigg

The toughest part of most of these swaps is finding the donor parts. Junkyards/Auto recyclers only seem to have vehicles 20 years old and newer nowadays. Anyone look at anything from the mid 90's on?

Not that I don't appreciate the information provided so far! Please keep any & all information coming!

I used to use the later model drums on these by having the holes in the hub drilled out to take the larger size studs.

George

Tadd, on T5's, I'm running one behind a (guessed at) 300 hp'ish 5.0. It's stood up to a lot of abuse. "However" It's never seen the kind of weight our trucks can put on the rear tires. I agree with Jerry, burnouts could be a problem. However T5's are easy to source and work on. In your' shoes if I already had one, I'd give it a shot, if it did fail, then look at other options.

On determining the ratio, the only way to know what you have is to read the tag (which you said is gone) and check one of the many online charts.....or rotate the input shaft and count the output shaft revolutions with the transmission in 5th gear. I'd go 10 input shaft revolutions while a bud counted the output turns. Be sure to mark both with a marker to make it easy to keep up. Divide the output turns by 10 and you have your od ratio.

Good Luck, RonR

You first need to find out what overdrive ratio your T5 has and then pick a rear gear to match. T5's range in OD ratios from 0.18 to 0.33 (or 0.82 to 0.67). A non world class T5 is a very weak transmission so if that is what you have I'd forget tire smokin. World class ones are stronger but still a wimp transmission as far as tolerating high torque. It is much easier to find w/c ones from Mustangs and they usually have the 33% OD. If you have a 4.57 rear and a 33% OD T5 then your final gearing with in overdrive would be 3.06 which is a very good road gear. An 18% OD T5 would give a 3.75 final---not so good.

Lot's of good advice there. I would have to agree. Before thinking about rearends, lets see what Trans. you got then go from there. Better yet, install it and see how you like it. There were almost 300 variations of the T5, so trying to say which one is good, which one is bad is nearly impossible. Truth be told, your rearend is about as strong as it gets, no need to swap it out unless you have to. Not to mention the 14 bolt is a big heavy brute. You'll probably lose some horsepower just trying to turn it's enormous brake drums.

The Mustang and F-body (Camaro) guys have been beating on the T5 for years. There's plenty of aftermarket parts and upgrades for it if you so choose. The 235 or 261 aren't really known for their abundance of horsepower or torque for that matter. I would think just about any T5 would hold up just fine.

Here's some good reading for you.
http://www.britishv8.org/articles/borg-warner-t5-id-tags.htm

http://www.fordmuscle.com/archives/2005/12/T5Rebuild/index.php

https://www.astroperformance.com/product/cluster-support-plate/

Thanks...
I was thinking the same thing about the Mustang's & Camaro's.

How much later of a model?

A lot of the older stuff is available on Ebay, but you have to shop smart and "Trust but Verify" before you commit to buy anything.
Jerry

You want a T5 out of a V8 camaro or trans-am to start, one that has a tag to properly identify. 1989 to about 93. These transmissions are what they call world class and has stronger gear sets. To further identify look at the front input shaft left and down a little is the front bearing retainer. If it has some writing on it and it's raised a bit it's a world class, un rebuilt transmission. If this cap is smooth and flush it's a non world class, forget it. Next Identify the o.d. Ratio, do the math to determine compatibility with your rear. I would suggest a professional rebuild to guarantee reliability. Also re-enforced o.d. bearing retainers for sale. T5 od rations are .63, .72, .73, .76, .86. The formula goes like this:

366x 60x rear gear ratio divided by tire size = rpm. (rpm x o.d.) = final rpm. 366 is the constant, 60 is the speed, rear gear ratio divided by tire diameter = rpm in 4th gear. Over drive rpm determined by multiplying this rpm by the o.d. Ratio. ANy of these parameters may be changed except the constant. MAke your self a chart, get out your calculator and have some fun. After a while you'll see the final gear you can live with given the 261 engine and the o.d. you are stuck with. My personal favorite o.d. ratio is .72

Cool.
Thanks!

Would it be possible to rebuild an S-10 T5 with new guts for a 89-93 Camaro/Firebird T5, or would it be smarter to start with a Camaro/Firebird T5 from that era, have it rebuilt, and swap tailshafts from the S-10 T5 I already have?

I accidentally ran across this thread. A properly maintained T5 transmission can handle 250 hp and 300 foot pounds of torque. Don’t plan on those numbers if you simply pull an old one out of a used truck or Camaro and install it into your truck. Have the T5 inspected and make sure it’s ready for service. End-play of the main shaft and input shaft is a very important issue.

The ideal combination is 0.72 overdrive with a 3.73 or 3.90 rear differential. The 0.63 OD is rather tall but an engine with plenty of HP can handle it. The 0.86 OD gear will work well with a 3.08 rear axle. The difference between a non-world class and world-class transmission strength is minimal and should not influence your decision.

Almost all 1993 and earlier S10 T5 cases have a Muncie pattern. Feel free to contact me with your T5 questions.
Jay

So far, I have a 0.72 overdrive and the stock 3/4 ton gears, 4.57, I believe. I'm on 16" wheels with very tall sidewalls...not sure of total height, but gotta be darn near 3 feet.

You may find these pages from my website helpful.
Case markings to help ID your T5.
How to determine the T5 gears inside a closed transmission case
VIDEO I made showing how to calculate gears by counting gear teeth inside an open T5

Ooooooh, Thanks!

And here's one to calculate speed and or RPM given your ratios and tire diameter.
http://www.onlineconversion.com/bigger_tires.htm

A "tall looking" 16" tire might be 31" tall unless its a real big wide one. Measure to know for sure, or look up your exact tire info from the manufacturer and see what the loaded radius is, or revolutions per mile, or close enough is the listed outside diameter.

Very helpful... I'll have to take a measurement.
Thanks!

Swap tail-shafts if you can find a camaro or trans-am V8 transmission front half. THen contact Lugnutz on this site, maybe he can find you what you need to get this done. Recommend if you are running a 6 cyl select your rear gear carefully to produce at least 2150 rpm in 1-1 high gear without Overdrive as you will be downshifting more than you know. it's a lot to think about before you build the transmission and selecting the final od ratio.

GREAT INFO!

Tadd,

He is the math with what you have; 366x60x4.57 divided by 31" = 3237 rpm in high gear without od. 3237 x .72= 2330 rpm with od. This is at 60 mpr. 3237 is too much in my humble opinion. I would be changing out the rear gear to something you can live with. Review previous e-mails. 3:73 as suggested by Lugnutz would be more reasonable.

T5 is a good cruiser trans. I blew up a pile of these in jeeps in the day in 4000# rigs with sticky tires though. I won't run them nowadays. Hard to find the good parts. Can't handle high input torque and a heavy rig. That's just my 2 cents. But then again I blow up nv4500's.

I have a T-5 with .72 overdrive behind a high pressure 235, with a limited slip 4.64 rear end, and 28 inch tall tires. It is wonderful for going as fast as I dare to go on the freeway and I can still pull out stumps with it. I believe that I could drag said pulled stump down the road at 65 MPH!
My next set of tires will be 31" tall which should dial me in to near perfect for what I need.

If I could only find one for my 3/4 ton.

If you have 4.56 in an ho52. Just look for a 4.10 . They are out there. With a t5 that will be a good cruiser.

I hope so.

The ho52 4.10 is not hard to find. Gm made millions. Honestly it's a great ratio for a 3/4 ton with a six.

Recommendations of where to find them? All the junkyards near me only go back 20 years..... usually, not even that far.

Hold on...

Perhaps one might look in 'junkier' parts of town where abd. vehicles occur. Older, smaller towns that don't have enough volume to justify frequent trips to recycler might be another place to look. Commercial shops(electricians, hvac, plumbers, etc.) might have dead vehicles out back, broken down vehicles 'other side of tracks.'

Ed

I live in flat land Indiana and I have 54 1/2 ton with a t-5 and a Nova 2.73 gears and 235-15 tires. It is great for cruising but get into serious mountains required shifting to 4 a lot. I do not spin tires unless on gravel When I need to get into traffic in a hurry.