Transmission wiring?

[BrownBadger]

Whoever replaced the transmission in my 85 T4WD before I bought it apparently decided it would be a good idea to cut all of the wires on both the transmission side and the wiring harness side. So now, I have 4 wires sitting in my engine compartment, but only 3 hanging off of the trans. I have two wires coming from the back-up switch, one wire coming from the 4wd indicator switch, and that's it. I dropped the rear trans support and felt around where the EL indicator switch should be, but could not find any wires.

So, a few questions.

Was the EL indicator on all year transmissions, or do I maybe not have the right year for my tercel?
If not, maybe I'll just do without the EL indicator on this car.

Since I have no harnesses anymore, does anyone know which wire from the trans goes to which wire in the harness? I tried looking at the wiring diagram, but was quickly lost.

[xirdneh]

early models have two plugs
late models three

[BrownBadger]

Yeah, I just did some searching and found that same info. So it looks like I have an early trans in my 85. Unfortunately I never drove it in 4wd before I pulled the engine for a rebuild, so I don't know if the rear-end was swapped as well.

Still, for the other wires, does anyone know which color wires I should connect?

[xirdneh]

if i was home i could go check
if i remember right the back-up lights are two wires red and black

[Petros]

the '83-84 has no EL indicator lite, only 4wd and reverse. the worst is the different front diff ratio are also different. they could have either swap out the front diff or the rear so they match, if they were that knowlagable. However based on the compatence of the wiring job, I would say that would be a long shot if they got that correct.

You can check your front and rear diff ratio without the engine. set the car so two tires on the same side of the car are on the ground, and the other two up in the air. 4wd engaged, parking brake off, and in 5th gear (actally any gear would work, just not neutral). Put a chalk mark on the front and gear tire at the saem clock postion (say straight down), than rotate one wheel through ten revolutions and stop with the chalk mark in the same place, the other wheel should also track the same, but if the other one clocks 9 revolutions, for the one ten (or 11 for the ten), than you have mismatched diffs.

This is not uncommon on cars this old. there is some idiot "interchangeability" guild running around the wrecking yard world saying all of the Tecel4wd trans are interchange across all years. this is not exactly correct, they will bolt up, but you have to change either the front or the rear diff ratios if you interchange the '83-84 with the the later years. No matter, many repair shops do this, as well as many DIYers who do not come to this forum for guidance. I got one T4wd cheap because after a trans change they had the rear diff fail. Reason, mismatched diff ratios (normally it is darn near impossible to wreck a Toyota rear diff, short of running it dry). The collage kid that owned it was out of money and had no idea what the repair shop had done to him. They had also messed up all if the carb vacuum lines on him, so it ran like crap.

I have purchased 2 Tercel4wd with mismatched front and rear diffs, it is not one of the first things I check for if the seller says they replaced the trans.

Good luck.

[BrownBadger]

So, I went did Petros' test to see if my front and rear were mismatched - got about 9 revolutions on the rear for 10 on the front - not a surprise since with only 100k miles it was on its second transmission and second engine. The engine had a bad rod knock and is currently being replaced by a built 4AC, the trans seemed fine, but I only drove it once before pulling the engine. And now I have some good and some bad news.

Bad news: They are mismatched - shame since the trans was a new replacement about 20k miles ago.
Good news: Dan in Reno just happens to be bringing me a low mileage 4.11 trans on Saturday - along with a VW Bus I am buying from him.
Bad news: I wasted some money, and way too much time replacing the seals on my old transmission while it was in the car.
Good news: This time I can do it with the trans out of the car, and since I've done them all before it should go much quicker this time.
Bad news: In replacing the trans all of the wires in the engine bay and on the trans were cut.
Good news: With the new trans I can get it wired up and now I will have EL light wiring.
Bad news: The previous owner, who only owned it for a few months, made this video of my Tercel off road: http://vimeo.com/71621728.
Good news: Even though it means potential damage to the rear diff, it sure looks like he had fun and I can't wait to get it back on the road.

A few questions:
Any tips or good threads on replacing the trans? Since the engine is already out I imagine it will be fairly straightforward from here.
Now I can only assume from the video above he was using 4wd. Is there any easy way to see if damage was done the rear diff?
With the new trans, are there any tests, etc. I should do before installing to make sure any potential problems are dealt with upfront?
Does anyone have a parts car that they can pull the engine wiring harness side connectors for the trans wiring?

[Petros]

the connectors use regular bayonet type contacts inside the plug. if you can not find a matching connector you can always splice the cut wire with just a bayonet connecter you attach within the other half of the plug. I would wrap it with electrical tape or heat shrink tubing to protect it and keep it from falling out.

useusally if the car was driven with mismatched front and rear diff either the rear ring and pinion looses all its teeth or the front one does, or the front diff input shaft fails. If neither has happened, than you are likely okay, but it might be worth pulling the rear diff to inspect the teeth to look for pitting, scoring or missing teeth, signs of stress, etc. It the gear faces have anything other than a smooth shinny surface and the correct amount of gear lash, it should be okay to use.