In depth analysis on C and S series transmissions [Archive] - Toyota MR2 Message Board

In depth analysis on C and S series transmissions [Archive] - Toyota MR2 Message Board Toyota MR2 Message Board > Toyota Engine Clubs > V6 Owners Group > In depth analysis on C and S series transmissions PDA

View Full Version : In depth analysis on C and S series transmissions

Jason.MZW2007-25-2006, 08:00 PMI just want everyone to remember the C and S series transmission share the same differential. That means ring gears are swappable between the two transmissions. Look to the end of this thread to find possible differential ratios for the S51 and S54. There are 2 other possibilities with the 3rd being the original.

Also keep in mind, Toyota rarely changes a number in the transmission series number, unless it is warranted by a change in actual gear ratios, not solely differential ratios. S is the series of the transmission, 5 is the number of gears, and x is the revision number. S5x = where x = 1 is the 1st revision, as is 0. The S51 was introduced in 1983 when the Camry was first sold in the U.S. The S52 and S53 are somewhere in between, but are no longer used. The S54 represents a change in transmission gearing, as did the S52 and S53. 4WD/AWD is denoted with an F or H at the end of an automatic or manual transmission revision number. 2WD is represented with an E at the end of an automatic transmission number only.

Here are the differences between the S51 and S54 for everyone to analyze:

S51 3.538 1.960 1.250 0.945 0.731 Diff: 3.944
S54 3.285 1.960 1.322 1.028 0.820 Diff: 4.176
S54 3.285 1.960 1.322 1.028 0.820 Diff: 3.944

The 3.944 S54 shares the same output shaft with the S51 and is available in the 90-93 Celica here in the U.S though many will refer to it as the S53 (because that's what it is, but the gearing is similar so we'll keep it simple). The output shaft driven gear has 18 teeth and the diff. ring gear has 71 teeth. The 4.176 S54 has 17 teeth on the output shaft driven gear and 71 teeth on the ring gear.

71/18 = 3.94444, while 71/17 = 4.17647. Which means that the S51 and S54 share the same ring gear with only the output shaft driven gear having been changed. The Celica also used a 71/19 combo which produced a 3.7368 diff. ratio which Randy Noll uses on his S/C'd V6. The output shaft from that transmission, however, is only compatible with S series transmissions made before Toyota increased the output shaft size, or before 05/90. There are other options if you keep reading.

Here is the S51 gearing compared with the E153 gearing:

E153 3.230 1.913 1.258 0.918 0.731 Diff: 3.933
S51 . 3.538 1.960 1.250 0.945 0.731 Diff: 3.944
E153 3.230 1.913 1.258 0.918 0.731 Diff: 4.285

1st, 2nd, and 4th are longer on the 3.933 E153, but everything except 1st is shorter on the 4.285 E153. Not a bad transmission for a V6 since the 3.933 E153 is used on the 1MZ. 5th gear is marginally longer on the 3.933 E153 vs. the 3.944 S51. So marginal, you wouldn't even notice. 3rd gear is the only gear the S51 has which is longer than any E153.

Now, take a look at the Yaris' C50 transmission and MR2 Spyder/Celica's C56:

C50 3.545 1.904 1.310 0.969 0.815 Diff: 3.722
C56 3.166 1.904 1.392 1.031 0.815 Diff. 4.312

Doesn't that look familar? They both share second gear, but this time they also share 5th gear. The C50 has a ring gear of 67 teeth with 18 on the output shaft. 18 teeth on the output shaft drive gear makes this ring gear 100% compatible with the S51. Because of the spead between the C50 and C56, the ring gear and output shaft were both changed.

The ring gear on the C56 is 69 teeth with 16 on the output shaft. The C56's ring gear might be a better match for the S54's output shaft drive gear since it's only off by one tooth, but that only gives you a 4.0588 ratio. Too much hassle for such little gain.

Take a look at the Echo's C150:

C150 3.545 1.904 1.310 0.969 0.815 Diff: 3.526

It's essentially the same transmission as the C50 except the output shaft. This uses a 67 tooth ring gear coupled with a 19 tooth output shaft drive gear, instead of 18 like the C50.

The Corolla's C59 uses a 67 tooth ring gear with a 17 tooth drive gear for 3.941. This is the perfect match for the S54's 17 tooth drive gear.

C59 3.166 1.904 1.310 0.969 0.815 Diff: 3.941

So the C series ring gears are as follows:
67 teeth
69 teeth

The S series ring gears are as follows:
71 teeth

The C series output shaft drive gears are as follows:
16 teeth
17 teeth
18 teeth
19 teeth

The S series output shaft drive gears are as follows:
17 teeth
18 teeth
19 teeth (prior to 5/90)

So this gives the S54 with 17 teeth these possible differential gear ratios: 3.941, 4.058, and 4.176.

This gives the S51 or 3.944 S54 with 18 teeth these possible differential gear ratios: 3.722, 3.833, and 3.944.

This gives the 3.74 S53 with 19 teeth these possible gear ratios: 3.526, 3.631, and 3.736.

It might be possible to use the 19 tooth output shaft from the C150 in the S series transmission, but that compatibility has not been proven. You'd also have to press the gears off each output shaft, which can be time consuming or expensive. These are only possibilities, not actualities. Gear lash between the output shaft pinion gear and the ring gear will be affected if you change one without changing the other. The gear lash may be too great for your particular application, like if you switched to a 67 tooth ring gear when the pinion gear was designed for a 71 tooth, and such. Compatibility has not been proven with such ring gears in the S transmissions as gear lash must be considered and measured.

The 3.944 S54 can also be found in UK 2nd and 3rd gen 3SGEs (JDM 3SGEs use 4.176 ratio for ALL years). The BEAMS 3SGE uses the 4.176 S54 just like the 91-95 MR2 and 94-99 5SFE Celica.

Here is a modified S51 with a 3.722 diff. ratio on 225/50/16s:
Modded S51 (http://mr2.phpwerx.net/turbocalc/gearratios.php?saved=H4sIAAAAAAAAAz2PSw7DIAxE7%2BI DRHwCScxhItTSikWaCFhUinL32hC6ws8jZsYeDZ4ZR4R38Amcx wnPiNJlEkAPRs%2FgIqrGclisYNadlak8NhbDMhpm03nSktkSC wSgRyK8oNtPSoG7MoVCOrZ1ix%2BWqI0UQvDYBf%2B9BVsTM84 IZT%2FW1roFkFpiCnyE5qPobw6PEvdqqhGUMjxZBJ8PUhgUwt% 2FwGf0WSkj3Xlrqdv0A34%2F00SIBAAA%3D)

Here is the 3.933 E153 on 225/50/16s:
1MZ based E153 (http://mr2.phpwerx.net/turbocalc/gearratios.php?saved=H4sIAAAAAAAAAz2PUQ6DIAyG79IDG KCCWg9jyMYWHpwGeFhivPtakT3Rr1%2F423qydGTqCd7BJ5g9D XRE0nNmAdgZVDBHMpV1N2kUxsbGjsJ9ZcX%2BYtt4QC3smBUB8 KMJXtDiJ%2BS4M%2FNQSPu6rPEjirfRSikpm%2FDfWzhjLzESl G1f6tZ1ANsSU5AjUI7ivzk8StyuUCQwxkrlCHze2QgYgn%2FgM %2Fo1lJDuvna82%2FkDwkTRGyIBAAA%3D) Enthalpy07-25-2006, 10:16 PMWow, nice research! Where did you find this information? Jason.MZW2007-25-2006, 10:53 PMI had to use math to figure out the C series transmission differential ring gear and output shaft drive gear teeth. Math helped me figure out exactly how many teeth each transmission used by using common denominators: the ring gear teeth and output shaft drive gear teeth from my very own counting of my S51 and S54 transmissions' ring gear and O.S. drive gear. It also helped to know the exact differential gear ratio of each transmission to compare the answers to the actual ratio.

Since the C and S series transmissions share differentials, I started with 71 ring gear teeth and 17 or 18 O.S. gear teeth. Then I started moving up and down with each one until I found the exact match for each transmission.

It seems Toyota likes O.S. gears between 16-19 teeth, and the ring gear teeth vary between them. This is a great example of Toyota's cost cutting techniques, and good news for people, like me, who are using the S51, or others who are using the S54. Weasy2k07-25-2006, 11:09 PMVERY VERY good info...sticky time!

Its a known fact that ring gears can move around..the only prob is that darn output shaft....

Ill be diving deeply into the tranny system in the fall when it dies down int he shop a bit (and more longer term projects come in)...i have been planning quite a few things for asome time now. Enthalpy07-25-2006, 11:31 PMI personally would like to put a taller 5th gear in both my MR2 and my 3VZ-FE (3.0 liter V6) Camry. Perhaps a slightly taller 4th would be nice as well. 1-3 are fine, so I don't want a different differential.

The taller gears in the MR2 would match the higher torque output I'm making and allow for better freeway economy. The taller 5th in my Camry would allow for bettery economy, and I know enough about engines to prevent the damage that can happen with overly-tall 5th gears.

Thanks for the information! Jason.MZW2007-25-2006, 11:50 PMAt 65mph, a 3.722 S51 will rev at approximately 2500rpm. At 80mph, it will rev at around 2900rpm. Unforunately for you E153 guys, I haven't found a transmission with which you can swap ring gears with. Oteck07-26-2006, 01:38 AMerm.... i swear some1 did a gear comparison ratio on the other board already, but us e153 have the solara v6 mt tranny for that Weasy2k07-26-2006, 12:25 PMyea the only thing you can do is get V6 or Celica Ring gears/out put shafts...for now... Oteck07-26-2006, 06:06 PMbut in the long run it's better to get a beat up 91 tranny and move the solara innards over, you get double/tripple synchros and what ever the 93+ tranny has to offer. and an LSD is a must too since it's already open :) Jason.MZW2007-26-2006, 08:15 PMbut in the long run it's better to get a beat up 91 tranny and move the solara innards over, you get double/tripple synchros and what ever the 93+ tranny has to offer. and an LSD is a must too since it's already open :)

It'd be better to just swap the middle casings. That way, you get the updated bellhousing with all bolts mounting to the 1MZ, unlike the early 91-92 E153s and all S51/S54s. Weasy2k07-26-2006, 09:01 PMyou have to change pout the endplate then too :) or else you dont got a rear mount Oteck07-26-2006, 10:09 PMi think it's actualy better w/o that bracket on the rear mount. you can have more clearance if you want to use the stock M/T headers Weasy2k07-26-2006, 10:13 PMthne you wont have a rear mount? Oteck07-26-2006, 10:16 PMid jsut be down to 2 bolts instead of 3 that hangs on the sides BonzaiCelica09-06-2011, 01:01 AMedited: jk I found out today on 12/30/12 that I just have a regular S54 4.176 final drive. ignore what urbandork said below urbandork09-06-2011, 04:01 AMlets not forget the C160 and C60 final drive gear ratio. I have a 4.529 final drive gear ratio currently in my S54 Helical LSD transmission. Greater acceleration!! :D

So your saying someone pressed the gears off of each output shaft and swapped out the output shaft and ring gear from a C160 or C60 trans into the transmission I sold you (which i picked up from a wrecking yard and then had the helical diff put in)... Perhaps but ill believe it when i see pictures of the ring and pinion gear when you swap out the LSD I had put into that thing.

I honestly didnt see a difference in gearing between that transmission I sold you and the one which was in the 6th gen celica that I had prior. Neither when either trans was on the car stock or with the 5sfte I did or the 3rd gen 3sgte I had later put in. (motor wouldnt really change any gearing but stated to underline the fact that I had had the experience with the both trans for a while.)

... Woke up later and tinkered a bit more

Doing the same math Jason.MZW20 did the C160 and C60 probably have a ring of 77 teeth and a pinion of 17 teeth.

77 / 17 = 4.52941176

If this is true then perhaps you could say that only the ring gear was changed from the stock s54 71 ring to c60/160 possible 77 teeth ring gear.

Although possible.... im still doubtful.... Awaiting pix brother bear. Hiu Bin06-28-2013, 05:10 PMBack from the dead:

So how exactly could I check whether my trans is 3.944 or 4.176? My it seems mine had the transmission replaced after tearing it out of the car. The tag that has the trans name on it is not on there, it was cut off.

I'm interested in getting getting taller gears/ratio, this one's too short. 50mph is at about 2500rpm in 5th gear. 65mph is at about 3000 or above, can't remember since it's been a while since I've driven the car.

However, I had a 93 celica that drove exactly the same in terms of rpm at certain speeds, so I'm inclined to believe it's been replaced with the taller diff S53 or as it's called here by Jason: "3.944 S54 with 18 teeth driven gear".

What ring gear (from what trans) would I need to make the 3.944 S54 a 3.722 final drive? TomsMR206-28-2013, 07:27 PMKeep in mind your car will be slower. Dropping the final drive drops power in all gears and hurts acceleration. The S54 with the lower final drive is from a gen3 3sge, only found in non US market cars. Unless you specifically bought one, its extremely unlikely you have one.

Best bet is to find an S51 and steal the 5th gear assembly out of it. You'll drop the cruising RPM in 5th only. It would be a fantastic swap for anyone using an S box. Hiu Bin06-29-2013, 10:31 AMKeep in mind your car will be slower. Dropping the final drive drops power in all gears and hurts acceleration. The S54 with the lower final drive is from a gen3 3sge, only found in non US market cars. Unless you specifically bought one, its extremely unlikely you have one.

Best bet is to find an S51 and steal the 5th gear assembly out of it. You'll drop the cruising RPM in 5th only. It would be a fantastic swap for anyone using an S box.

It was mentioned in the OP that the S54 with lower final drive is the S53, which is found in the 90-93 Celica GT and GT-S. If that's true then it's highly likely, since there's more of those around PR than of my own (I'm in this forum for the sharing of knowledge of the same engine/trans platform, but I own a 6GC)

Anyhow I know I'll get a loss in acceleration, but instead I'll pick up on traction and MPH in all gears which I'm interested in. S54 gearing is too short for turbo. Hiu Bin07-09-2013, 08:06 PMIt was mentioned in the OP that the S54 with lower final drive is the S53, which is found in the 90-93 Celica GT and GT-S. If that's true then it's highly likely, since there's more of those around PR than of my own (I'm in this forum for the sharing of knowledge of the same engine/trans platform, but I own a 6GC)

Anyhow I know I'll get a loss in acceleration, but instead I'll pick up on traction and MPH in all gears which I'm interested in. S54 gearing is too short for turbo.



Answered my question. I could POSSIBLY use a Yaris C50 ring gear of 67 teeth for a 3.7xx final drive. A C56 ring gear would give me 3.833. Powered by vBulletin® Version 4.2.5 Copyright © 2026 vBulletin Solutions Inc. All rights reserved.