s51 in my '91 ST184?

Numbchux

New member
My '91 ST184 convertible has some sort of internal differential damage causing the CV output seal to leak. So I think I'm going to just swap the whole transmission...

While I'm at it, I'd like to get taller gears, 3400 rpm @ 75 is a little rediculous. So, according to the Toyota S transmission Wikipedia page, S51 would have similar 1-3, with a taller 4-5....perfect! Not a major change, but it would bring the rpms down to about 3k @ 75mph.

There's a fairly local junkyard with a transmission from a '99 2.2l 5MT Camry listed on car-part in good shape for a great price. This should be an S51, right?

So I've been searching like crazy, and I can't seem to find any detailed info about this swap. Sounds like it should be pretty straightforward...but I'd like to make sure. I work at AutoZone, and I've been comparing the parts around the transmission for signs of problems, and the parts diagrams on Partsouq.com....and I haven't found anything major. I also found an ebay ad with an S53 (searched for the '91 Celica), but I haven't found much for pictures of an S51.

CV axles use 20 spline inners, output seals are the same, starters are different, but the only difference is the location of the battery post, clutch/flywheel/slave cylinder are the same, reverse switch is the same.

The things I have found that I'm not sure about. Mounts. The way the engine/transmission is mounted in a '99 Camry and '91 Celica are very different. Can I swap the mounts/brackets from the S53 over to the S51?

Speedometer. Just from the parts diagrams, it looks like the '91 cable would replace the VSS on the '99 without too much trouble...

Shifting. Again, from the parts diagrams, it looks like the shifter cables are very similar.



Sound like I'm on the right track? Anything I missed?
 

fussellbug

New member
Yes the 99 Camry does use the S51 transmission. The S51, S53 and S54 transmissions are interchangeable. There are very minor exterior differences that should not affect your swap. The major differences are internal, such as gear ratios and synchros. The engine mounts are different for each car model but they attach to the transmission using the same holes on the transmission cases. I am currently running the S54 from a JDM ST202 Celica in my 1990 GT-S and the only mods I had to do were to swap the electronic speed sensor with my cable drive speedo adapter and put my 1990 engine mount on the S54.

If all you want is better cruising fuel economy (lower RPM), you can just swap your 5th gears with those from the S51. There was a lot of talk about this in the Beams 3S forums a while ago.
Part Numbers:
33336-33020 5th Gear
33428-32042 5th Driven Gear

A walkthrough of how to do the gear swap:
http://www.twobrutal.co.uk/forum/sh...54-(Mk2NA)-5th-gears&highlight=fifth+gear+s54
 

Numbchux

New member
fussellbug":2ideo9fv said:
Yes the 99 Camry does use the S51 transmission. The S51, S53 and S54 transmissions are interchangeable. There are very minor exterior differences that should not affect your swap. The major differences are internal, such as gear ratios and synchros. The engine mounts are different for each car model but they attach to the transmission using the same holes on the transmission cases. I am currently running the S54 from a JDM ST202 Celica in my 1990 GT-S and the only mods I had to do were to swap the electronic speed sensor with my cable drive speedo adapter and put my 1990 engine mount on the S54.

If all you want is better cruising fuel economy (lower RPM), you can just swap your 5th gears with those from the S51. There was a lot of talk about this in the Beams 3S forums a while ago.
Part Numbers:
33336-33020 5th Gear
33428-32042 5th Driven Gear

A walkthrough of how to do the gear swap:
http://www.twobrutal.co.uk/forum/sh...54-(Mk2NA)-5th-gears&highlight=fifth+gear+s54


Awesome!! Thanks for confirming that for me.

I've seen the 5th gear swap discussion several times, it's part of what gave me the idea. But, my front differential is damaged from a severe suspension impact before I got the car. I've opted to just get a whole used transmission instead of trying to rebuild this one (although I will hang onto it. I've seen several posts about the S53 having strong gears and better syncros....so if the S51 doesn't hold up, I might be able to make one good transmission between them).


I had another thought this morning on confirming whether this would work. I was looking at the parts diagrams.....maybe it would be worth looking at the application list for the bellhousing section of the transmission case (where those 2 mounts bolt on)....

http://www.toyodiy.com/parts/xref?s=3110533030&mU=on

Yep, the '99 5SFE Camry and '91 ST184 are both on that list. I'll pick up that transmission next week, and hopefully once the snow melts, I'll get it swapped in.
 

fussellbug

New member
front differential is damaged from a severe suspension impact before I got the car.

If that's the only damage, I would definitely keep the S53 and when the S51 is in need of a rebuild, you can use parts of each to get the better synchros and the better cruising RPM.
 

Numbchux

New member
Just following up. Did the S51 swap this weekend. Exactly as fussellbug said, it was a direct replacement. All the mounts were in the case, just had to swap over the brackets and such, and it bolted right in. Most of those threaded holes were not in use in the Camry, so I chased them with a tap (most were 10x1.25) before installing. '99 VSS came out, and '91 VSS/Speedo cable went right in it's place.
 
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