The Ford Barn

flathead 53 · 04-05-2018, 04:20 PM

I just bought a 1985 RT-170 3speed overdrive transmission that I want to install in my 1953 f-100 pick up with a 51 merc flathead. any one done this swap? One problem I know of is the stock clutch linkage on the 53,the bracket bolts to the original transmission. other then that any advice would be of help.

rotorwrench · 04-05-2018, 05:59 PM

On the T170, which one do you have? There are two types that have been used that have integral stick shift. The SROD has the single rail that shifts from the tail shaft housing. The TOD or RTS type has the more conventional top turret type shifter as used in trucks. There are three different ratios for different applications of the TOD. Of the three, two are in the usable range with one taller than the other and the third is almost too tall for a flathead. It was set up for 351 2 & 4WD and lower geared 300 6-cylinder 4WD applications.

On your F100, does it still have the original bell housing and clutch used in 1953? I think it was a one year only and may or may not be easy to modify for the top loader butterfly type bolt pattern. Many of the 8BA era flatheads have the narrow Borg Warner 4-bolt pattern that was used up into the early 60s. Especially the Ford cars and later Mercurys. The RTS and maybe some of the truck type SROD transmissions have drillings for that pattern inboard from the late type bolt pattern but only two are drilled through. Some folks weld up mounts to use one or both of the upper outer mount bolt holes. You may have to fabricate a mount to use the original clutch or change to a hydraulic set up.

I think this question has been asked before but at any rate, I haven't seen a complete answer for it yet. These transmissions have an aluminum case so they aren't the strongest gearbox but they would be nice behind a moderate flathead. I'm not sure if the 84 thru early 87 F150 or Bronco clutch disk can be used or not but it depends on the size of the pressure plate used. Something can be made to work OK.

Most of the info out there for the T170 FT RTS TOD transmission is for the Model A cars since they have been finding there way into them for over 20 years now.

flathead 53 · 04-06-2018, 03:32 PM

Ihave the RTS, the big problem is the clutch bracket on the 53 ,it bolts to the side of the original transmission . this is the same on 53to 56 f-100.

Ol' Ron · 04-06-2018, 04:43 PM

I used an 8BA ford passenger car steel bell housing. bored out the regester to match the trans, welded on some flanged for the bolts. Used the stock clutch linkage. Had to shorten the drive shaft, but i think the U joint fit. can't remember that.Mine is from a 6 cyl, but the engine is a stock 280 ci Flathead wit EAB cam

rotorwrench · 04-06-2018, 05:29 PM

On the model A conversions, a bracket has to be fabricated to hold the pedals since that was the way they were attached in the original transmission installation. It bolts on with the left side transmission mounting bolts. Most are home shop fabricated. I'm sure that there is a way it could be done for your clutch set up. Do a search in the model A section and there is info there.

The RTS TOD transmission has a 6 1/2-inch protrusion of the input shaft if I remember correctly. You will have to see how that compares to the original transmission set up. A shim or possibly an adapter could be necessary between the trans and housing if its longer but I've not heard anyone mention much about that possibility yet. If it fits then I'd sure like to know. The model A installation is different than the later V8 is due to the completely different bell housing set up on them. There are half bell adapters available for the top loaders but they use the rotating fork type of clutch equalizer shaft. Yours just needs a bell crank mount for the clutch pull rod.

flathead 53 · 04-07-2018, 05:11 AM

Sponsored Links (Register now to hide all advertisements)

Any one have a picture of the fabricated bracket used on the model A with this transmission

rotorwrench · 04-07-2018, 08:29 AM

From the model A forum, post number 66. #3 shows a pedal mount and there is also a hand brake mount for the other side.
https://www.fordbarn.com/forum/showt...ht=F150&page=4

This just illustrates what was done for that problem. If your mounting needs to be farther to the rear, the tail shaft mounting bolts may have to be involved to get the support you need. Search strings on the site should include either T170 or F150 to find other info. You can also google it and find Ford Barn links that way.

04-05-2018, 04:20 PM	#1
flathead 53 Senior Member Join Date: Jul 2011 Location: central nj Posts: 717	1985 ford RT-170 trans,in a 53 f-100 I just bought a 1985 RT-170 3speed overdrive transmission that I want to install in my 1953 f-100 pick up with a 51 merc flathead. any one done this swap? One problem I know of is the stock clutch linkage on the 53,the bracket bolts to the original transmission. other then that any advice would be of help.

04-05-2018, 05:59 PM	#2
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,440	Re: 1985 ford RT-170 trans,in a 53 f-100 On the T170, which one do you have? There are two types that have been used that have integral stick shift. The SROD has the single rail that shifts from the tail shaft housing. The TOD or RTS type has the more conventional top turret type shifter as used in trucks. There are three different ratios for different applications of the TOD. Of the three, two are in the usable range with one taller than the other and the third is almost too tall for a flathead. It was set up for 351 2 & 4WD and lower geared 300 6-cylinder 4WD applications. On your F100, does it still have the original bell housing and clutch used in 1953? I think it was a one year only and may or may not be easy to modify for the top loader butterfly type bolt pattern. Many of the 8BA era flatheads have the narrow Borg Warner 4-bolt pattern that was used up into the early 60s. Especially the Ford cars and later Mercurys. The RTS and maybe some of the truck type SROD transmissions have drillings for that pattern inboard from the late type bolt pattern but only two are drilled through. Some folks weld up mounts to use one or both of the upper outer mount bolt holes. You may have to fabricate a mount to use the original clutch or change to a hydraulic set up. I think this question has been asked before but at any rate, I haven't seen a complete answer for it yet. These transmissions have an aluminum case so they aren't the strongest gearbox but they would be nice behind a moderate flathead. I'm not sure if the 84 thru early 87 F150 or Bronco clutch disk can be used or not but it depends on the size of the pressure plate used. Something can be made to work OK. Most of the info out there for the T170 FT RTS TOD transmission is for the Model A cars since they have been finding there way into them for over 20 years now. Last edited by rotorwrench; 04-06-2018 at 09:46 AM.

04-06-2018, 04:43 PM	#4
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,861	Re: 1985 ford RT-170 trans,in a 53 f-100 I used an 8BA ford passenger car steel bell housing. bored out the regester to match the trans, welded on some flanged for the bolts. Used the stock clutch linkage. Had to shorten the drive shaft, but i think the U joint fit. can't remember that.Mine is from a 6 cyl, but the engine is a stock 280 ci Flathead wit EAB cam

04-06-2018, 05:29 PM	#5
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,440	Re: 1985 ford RT-170 trans,in a 53 f-100 On the model A conversions, a bracket has to be fabricated to hold the pedals since that was the way they were attached in the original transmission installation. It bolts on with the left side transmission mounting bolts. Most are home shop fabricated. I'm sure that there is a way it could be done for your clutch set up. Do a search in the model A section and there is info there. The RTS TOD transmission has a 6 1/2-inch protrusion of the input shaft if I remember correctly. You will have to see how that compares to the original transmission set up. A shim or possibly an adapter could be necessary between the trans and housing if its longer but I've not heard anyone mention much about that possibility yet. If it fits then I'd sure like to know. The model A installation is different than the later V8 is due to the completely different bell housing set up on them. There are half bell adapters available for the top loaders but they use the rotating fork type of clutch equalizer shaft. Yours just needs a bell crank mount for the clutch pull rod. Last edited by rotorwrench; 04-06-2018 at 05:35 PM.

04-07-2018, 05:11 AM	#6
flathead 53 Senior Member Join Date: Jul 2011 Location: central nj Posts: 717	Re: 1985 ford RT-170 trans,in a 53 f-100 Sponsored Links (Register now to hide all advertisements) Any one have a picture of the fabricated bracket used on the model A with this transmission

04-06-2018, 03:32 PM	#3
flathead 53 Senior Member Join Date: Jul 2011 Location: central nj Posts: 717	Re: 1985 ford RT-170 trans,in a 53 f-100 Ihave the RTS, the big problem is the clutch bracket on the 53 ,it bolts to the side of the original transmission . this is the same on 53to 56 f-100.

04-07-2018, 08:29 AM	#7
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,440	Re: 1985 ford RT-170 trans,in a 53 f-100 From the model A forum, post number 66. #3 shows a pedal mount and there is also a hand brake mount for the other side. https://www.fordbarn.com/forum/showt...ht=F150&page=4 This just illustrates what was done for that problem. If your mounting needs to be farther to the rear, the tail shaft mounting bolts may have to be involved to get the support you need. Search strings on the site should include either T170 or F150 to find other info. You can also google it and find Ford Barn links that way.