2 months ago a garage swapped my knackered 700R4 for a good box that i had laying around ( in my '87 camaro ). The car was taken out yesterday for the first time since the swap and for an hour everything was fine then i saw smoke pouring from the sides of the car so i pulled over as soon as i could . By the time i had pulled over (200 yards ) i had lost all gears and there was a huge amount of transmission oil under the car as well as a long trail behind me.

I looked underneath and could see oil all around the passenger side and smeared around the exhaust , hence the smoke ,

The car now will not select any gears due to the lack of fluid. Any idea what it could be ?? i know the mechanic changed the front and rear seal but i'm wondering if he put them in right or wether he cracked a trans cooler pipe ?? its going ont he ramp tomorrow but i'm sooo p*ssed at the fact it could mean a rebuild

Any thought guys

 

Losing it all at speed is rough man. I feel for you. I can't even imagine what was going on inside the trans as it quickly lost fluid but I know it isn't good.

There are only a few places you could lose fluid that quickly:

1. trans cooler lines. If they popped, there ya go. Its easy enough to think you got em in - especially after a few minutes of swearing at em - when you really only crossthreaded it.

2. Big honkin hole in the pan, as if you ran over something big. Loose bolts wouldn't do this, the pan holds at least 5 quarts, and to think that more than half the bolts came out all at once is ludicrous.

3. Rear end - but the driveshaft would have had to come out. It only sort of drizzles out and not all of it would be gone either.

4. Sudden giant hole in the TC. Again ludicrous as you'd feel it first, those things are solid.

5. Front seal is possible, but not very likely - the TC wouldn't go back on if it wasn't perfect.

6. TV, Speedo, Vent aren't options. Those holes aren't under pressure and don't explain the amount of fluid.


I'm gonna put my money on #1.

 

Thanks for the input

My mechanic dropped the box today to find the trans cooler lines in perfect condition and the front seal in good condition

I rang and spoke to someone who knew a bit about the 700R4 box and he said it could be the bush behind the front seal as they can wear out and cause to much pressure on the front seal ????

does that sound about ringht ?

 

Sometimes the pressure pushes the bushing out. There is a mod to the earlier pumps to help prevent this. I always lock tite the new front pump bushings in on a rebuild.
They also make a teflon coated pront pump bushing. I recommend using it next go around.

 

Floor guy you were bang on mate.

Transmission guy said the front bushes were worn

 

Well as i said the front bushes were worn and so they were replaced and the tranny was bolted up yesterday morning.

The leak is now sorted but the transmission wont select 3rd now ???? I'm wondering that when i lost the fluid and kept going to find a safe place to stop that maybe i fried the box ??

I'll whip the governor out tomorrow to see if its got gunk all around it. Could the symptons that i've got now have been caused by loosing the fluid

 

Will the can not shift to 3rd, or does it shift and slip badly?

 

Sounds like it wants to shift but doesn't

 

The governor typically will not allow an upshift from 1st gear, if the valve is stuck, or the gear is stripped.
Check it though, goos place to start.
If that does not work, a valve may be sticking in the valve body.

 

Thanks

Can i have your honest opinion on this box floorguy. I'm sick of messing with mine and i thinking of buying this box.

https://www.thirdgen.org/forums/engi...eet-strip.html

Craig

 

Tough question to answer solidly. The link in the for sale section takes you to the listing at Summit racing. It does not describe what is actually in the trans. Because I have no 1st hand experience with Hughes products, I cannot answer accurately. Do you have local people that can do a good rebuild of your unit? I would imagine that they are more difficult to find in your neighborhood.

 

Floor guy there are 3 companies that are capable of rebuilding a 700R4 in the U.K and the cheapest qoute is £995 so about $2000 for a basic rebuild.

I've arranged a friend of mine to stick a transmission in the container he is shipping his car in and that will be free so you can see why its far cheaper to go down this route

I just need to be certain the tranny i buy is a good one due to my location

 

Wow.
I guess we are luck here in the states. I built one for a friend in spain, and they wanted $4000 US dollars to rebuild his. Another friend in Italy had me do 2 for his car(and a friend) because pricing was similar.
Pro-Built is a forum sponsor and has a great reputation. I bet he can be a huge help. I buy parts from Dana(pro-built) and am very pleased.
I have a corvette forum member in England asking about parts and info. I wonder if he is using 1 of the 3 guys you mention?

 

I would put my house on the fact he's using either

GM auto's
Alders automatics
or Penn auto's

They are the only three that can be trusted with a 700R4.

I'll have a look on pro-builts website. I really want to get this thing sorted i've already spent a fortune on two boxes that are now good for nothing.

The March transmssion looks a good box but again i have no idea whether it'll need a rebuild straight off the bat , a lot of miles can be covered in 2.5 years,.