Rear differential ratio question

[vietnamvanman]

Hi all,

I've been searching the Net for evidence of the rear diff. ratio. The problem is i have an LE 86 (Actually, its model year is 87). It is an automatic 2WD that had been converted to manual sometime before. I don't know if during that conversion, previous owner changed to rear diff or not OR the rear diff was changed somtime before because it was broken ? Who knows ? Because i don't have service history of the VAN.

I fell it is runs like a truck, especially with 1st and 2nd gear. And on highway it's 3000RPM at 100km/h. i want to change to a faster diff. I've been searching for gear ratio and found a lot of variations from 4.77, 4.3, 4.1 and 3.7. I guess 4.77/4.3 are for 4WD automatic/manual ?

I open my diff and found that it is currently 4.3. I want it faster so i changed to 3.7. Already done. The VAN runs smooth, faster on highway and the speedometter is correct again (the speedometter was slower before change from 4.3 to 3.7 diff). Now, it's 1600RPM at 100km/h. Wow, I'm happy with the result.

However, i'm still wonder what are the stock rear diff ratio for a 2WD manual/automatic VAN ? Are they same or different ? And are they different from 2WD to 4WD ?

I now 3.7 diff is used on Previa super charged.

Thank you & regards,
Tinh

[timsrv]

The search feature is your friend :yes: http://www.toyotavantech.com/forum/showthread.php?771-rear-diff-question&highlight=differential+gear+ratio

[vietnamvanman]

The search feature is your friend :yes: http://www.toyotavantech.com/forum/showthread.php?771-rear-diff-question&highlight=differential+gear+ratio

Hi Tim,

I did search all this site and google. i read above thread already but still not answer my qestion :wall:

My question is diff ratio for a 2WD manual. From above thread and other information i know the ratio vary as bellow. Please correct me if i'm wrong.


4WD automatic ratio is 4.77
4WD manual is 4.3
2WD automatic cargo (your picture in above thread) is 4.3
2WD manual passenger (Wagon) ???


My question is above in RED.

From some information and my best guest, it would be 3.7... 41/11 for the answer. I can not verify this by the tag because my VAN is 2WD automatic Wagon which had been converted to manual sometime before. I assume the conversion use a G52 tranmisssion but i also don't have way to verify this.

I know you have about 20 VANs, so you could answer my question pretty easy :). What the tag on the 2WD manual passenger (wagon) says ?

Thank you & kind regards,
Tinh

[timsrv]

I don't currently have any 2wd vans with manual transmissions (no tags to read) but I believe the ratio to be the same on the 4wd as it is on the 2wd. Tim

[vietnamvanman]

I don't currently have any 2wd vans with manual transmissions (no tags to read) but I believe the ratio to be the same on the 4wd as it is on the 2wd. Tim

I have just passed by a Garage and see a VAN there. I checked the tag on the VAN. It is an 2WD manual. The tag says: E312G53.

It means the diff is 7.1'' with a ratio of 3.9 and use the G53 transmission. It's interesting. I forgot to check it if the VAN is a cargo or a passenger. Do you know if the passenger version has a manual transmission ? Or the passenger only has the automatic ?

[wirewrkr]

I'll chime here because I have a 1988 Cargo Van with 5-speed and 2 wheel drive. Maybe this will help the original poster.
My door plate lists it as a F292, which translates to 7.5" gear with a 4.1 ratio.
The chart on pdf file is from 89-93, is there an older one available Tim, or is does that one carry true for older vehicles as well?

[timsrv]

I would think the codes hold true throughout the years. Tim

[wirewrkr]

Works for me!

[vietnamvanman]

I'll chime here because I have a 1988 Cargo Van with 5-speed and 2 wheel drive. Maybe this will help the original poster.
My door plate lists it as a F292, which translates to 7.5" gear with a 4.1 ratio.
The chart on pdf file is from 89-93, is there an older one available Tim, or is does that one carry true for older vehicles as well?

Thank you for the information !

So far, I've seen the Vans with 5-speed and 2 wheel drive use F292 (7.5''/4.1 ratio) and E312 (7.1''/ 3.9 ratio). I haven't seen a VAN with 3.7 ratio like the rear diff i'm having :clap:

Anyway, I'm happy with the switching from 4.3 to 3.7

Another issue is my speedometer is not correct above 70km/h. Above 70km/h, it's slower than the actual speed of the vehicle while bellow 70km/h it matches with the real speed (by GPS).

I've changed the speedometer driven gear but haven't fixed the issue. I guess it is a slip in the speedometer gauge because i see the hole where the speedometer cable plug in is in round shape rather than square shape.

Anyone has experience in this ? Thank you very much !

[theojo]

5 speed 84 LE with windows. Built August 83. E312 which is the 7.1 with 3.909 ratio.