I found a really cheap T-18 Borg Warner Top loader 4-Speed Manual Trany locally, and I was curious if I could make it work on my stock I-6 223 engine in hopes of getting rid of my stock 3-speed heavy duty column shift trany.

I just like the idea of a floor shift trany instead of column shift, but perhaps that is sacrilegious.

The guy says it came out of a 4x4 1970 Ford Bronco, but based on my research, the T-18 trany was used in the 1956 - 1990 Ford trucks. My concern is two fold. First, does it make a difference if it is a 4x4 trany, and will it work on my 1955 2x4 F-250? Second, can I make this trany mate up to my 223 I-6? Or are there better 4-speed manual floor trany choices available that would mate up to my 223 engine better?

Please let me know soon. Thanks.

I have pictures of the trany if you want me to post them up if that would help.

 

What you have there is the replacement "granny low" truck 4 speed that replaced the old B-W T-98 in 1966. It was made until 1990. It would be a horrible tranny behind a 6 cyl due to its ratios. Your regular 3 speed is already better that the three synchronized gears that the T-18 has. The only reason for the T-18 is in a 4 x 4 for rock crawling. It is also very heavy. There are plenty of 2WD T-18s, but if you have a 4WD version, it would be expensive to change it to 2WD. If you want a different tranny, look for a T-5 out of a Chevy S-10 which would give you an overdrive tranny, and the S-10 has the gearshift lever at the back of the tranny instead of on the back of the tailshaft which in a truck, is almost under the seat. The 223 has a lot of torque and would pull the overdrive ratio quite well, giving you a lot of gas mileage. It would be perfect to use with the most commonly used rear axle ratio in a 6 cyl. truck, a 3.92.

Regards,

Alan

 

The 223 could be ordered with a Borg Warner T-98 four speed crashbox. The bellhousing is different from the standard 3 speed don't know about the HD 3 speed maybe you lucked out. The T-18 is a later version but if it was behind a 302 I believe the input shaft "stickout" is less than you need plus the 4 x 4 version bolts to a transfer case rather than having a yoke to bolt your driveshaft to. Google Advance Adapters, they make adapters for the 4 x 4 set and have some useful dimensions in some of their PDF files.

 

A T98 4 speed should be a direct bolt in with the correct bell housing. T98s are pretty much indestructable and IMO a much better trans then a T18.......especially be hind a six. I have one with over 200k miles on it and still going!! T/M

 

If, you want a tranny with a low gear of 3.10, second oif 1.49 (extreme wide ratio), no overdrive, extremely heavy, hard to shift, and IMHO, very little difference between a T-98 and the latest T-19 other than better synchronizers, helical gears, and better shift forks. In other words, why would you want a heavy duty truck transmission in a 1/2 ton truck which is not going to haul anything? Why would you not want a nice floor shifted overdrive transmission which would be easy to shift and one that has excellent ratios? The existing bell housing is all you need to mate to the T-5, as there is an adapter package that allows it to bolt to virtually any three speed bellhousing. The front of a T-5 is the same in the Chevrolet and Ford versions, but the Chevy S-10 version has the shifter in the best position for a F-100 truck.

Some responses are missing the point:

1. A T-18 4WD model won't work for a 2WD truck, as it is made to mate with a transfer case only, has no tailshaft, would require a new mainshaft and tailshaft.

2. Yes, a 223 came with a T-98 originally if it was ordered that way.

3. A T-18 and its upgrade, the T-19 are better than the T-98 in noise and in shifting, but all are not good transmissions for a 1/2 ton pickup with a 6 cylinder which is going to be used for light hauling or just transport.

4. The friction coefficient of a 4 speed heavy truck transmission was not even mentioned. Just figure what horsepower is required to turn the countershaft, idlers, etc in the 90 weight gear oil as compared to a smaller light transmission. A short time ago, gas was over $4 a gallon. Why would you not want a transmission that was efficient and would save on gas as well as one that would be easy to shift?

Regards,

Alan

 

Alan,

Thanks for the info. Keep in mind though that my truck has a Dana/Spicer 60 rear end with 4.88 gears, and my truck is an F-250 not a F-100. I am not sure what model trany I have in my stock truck, but I know it is the Heavy Duty 3-Speed that came with it.

Like some other have suggested in the past, I would not only need to swap out the rear end, but the trany as well to get better mileage and highway driveability.

 

The T-98 is an excellent (& very strong) transmission. .....They are fully supported with rebuild parts etc...

The T98 Transmission - Novak Conversions
Borg Warner T98 : Tellico 4x4
Borg Warner T98 4 Speed repair parts and overhaul kits. - Drivetrain.com

I have a very nice T-98 with tail mounted parking brake, bell housing, new: clutch, pressure plate, pilot and throw-out bearings, that I would be using if I wasn't putting an automatic trans in my F-600. (if someone in the NW is interested! i don't think it would be cost effective to palletize and ship)



If you use synthetic oil in it I would bet you wouldn't be able to tell much difference in mileage between it and any modern (non-OD) trans.

I don't think there are very many people with old trucks on here that do a lot of worrying about gas mileage with these trucks.

They're usually not used as commuter cars. That said, I fully expect 15 mpg or better with my F-600 (when empty of course on a flat freeway!)


Cheers,


Rick

 

Hmmm.... I guess my plan was to use synthetic in all stuff on this truck that requires oil. I guess I just need to finish rebuilding all of this stuff, try it out first and then decide if I want need a different trany set up.

 

Well, then, it is the same as mine. The T-5 has a .7 OD ratio which would give you a 3.41 final drive ratio. Also, since the Dana 60 is a high dollar full floating axle rear end, it is easy to put in a 4.11 as a final drive ratio. The Dana 44 and 60 are conventional hypoid style and are more efficient than a 9" Ford which has the pinion centerline below the center of the ring gear, causing more friction.

Also, the drag of a T-98 or T-18 is due to the size of the cluster gear running in the oil, and the thickness of the oil itself. More modern transmissions are made to use light oil of 30-40 weight, not 90 weight. It is the oil viscosity, not the slickness or lubrosity of the oil that makes the difference. But the size of the cluster gear and its bearings is a part of the overall parasitic loss of such a large transmission.

If your rear end were regeared to 4.11 and an OD was used, the final drive would be 2.87 in OD. It would be 3.41 with a 4.88. either would be a lot better than what you have now with 1:1 in high gear. I changed my Dana 60 to 4.11 and am using it with a 700R4 Automatic OD which is .70 in overdrive.

Regards,

Alan

 

Alan,

If that is what you have, what kind of speeds are you running at in each gear, and especially the top gear? Also what RPM's are you running at those speeds with that set up?

 

If you want to be able to compare gears ratios and tire sizes with RPM, you need to use a gear calculator.

Fatboy Raceworks Graphical Transmission Gear Ratio Calculator

I simply calculated (using the actual tire diameter) how many tire revolutions my tire would make in a mile and calculated it at 60 mph (1 mile per min) which gives me rear tire revs per min.

Then you simply multiply that by your rear ratio and any overdrive (if installed) to get engine RPM (at 60)

Here's a better one http://www.angelfire.com/fl/procrastination/rear.html


That calculator above is simple enough to use. Search around, there's a bunch of them out there. Most will either allow the use of the actual tire size in inches or the tire size in metric standard size etc.

 

The T -18 is more up to date than the T-98,both are good if not great gear boxes,I dont see why a T-18 would be a bad choice behind your 223.