What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Is my 700R4 dead?

W

WantedaDodge

1/2 ton status
Joined
Dec 16, 2004
Posts
282
Reaction score
0
Location
Eugene, OR
I was going up a steep gravel hill and hit a bump, when I got to the top, I found that the Trans cooler line came off and dumped a bunch of fluid. I hooked it back up and put my spare quart in. The was a little red on the dip stick after I let it idle in neutral for a little bit.

I put it in drive and everything worked fine. I tried backing up and it wouldn't do anything! I tried and tried, couldn't do it. So I put it in 4 wheel and turned around in drive(had to go throught some brush).

I drove about 5 miles to the nearest store. Bought 2 quarts of ATF and filled it up, so I thought. Drive is working fine, not slipping, I drive back to my shop, Check it again Still a quart down so I put another one in and let it idle for a long time. I check it and it's completely full know, up past the full on the dip.

Reverse still won't work.

Any ideas? A buddy of mine thought I might have accidently screwed up some linkage when I turned around in the brush. It doesn't make any noise it just doesn't engage.

So am I screwed? I was thinking about driving it up on some ramps and then putting in reverse and letting it coast down to see it will catch.

Any ideas? I'm desperate! Can't afford a trans revuild right now!!!
 
WantedaDodge said:
The was a little red on the dip stick after I let it idle in neutral for a little bit.
Click to expand...
you can do it in park also, no difference on a GM tranny

my guess is yes, reverse is probably toast. normally i would ask if the fluid is burn or brown, but you probably added enough that it looks good.

if you can get drive and park then its not the linkage, as reverse is between these.

how many miles are on the tranny? it may have been on its last leg and loosing the cooler line killed it completely
 
big83chevy4x4 said:
how many miles are on the tranny? it may have been on its last leg and loosing the cooler line killed it completely
Click to expand...

about 40,000 miles

Can I just replace the reverse servo? in forward, things feel fine.
 
It doesn't seem like that would be enough to kill your reverse unless the hill was real long but usually when it goes you'll hear it when you try to use that gear. Also if reverse is gone don't suprised if you lose all the rest. when a gear goes in a tranny its like a dominoe affect becuase of excess metal shavings.

Is it complety quite when you put it in R? It kinda sounds like you have it in neutral but I don't know jack about how the insides of a tranny work besides the servo and valve body.

good luck..
 
yea it's quiet... no noise
just revs up when I step on it.

I've had a reverse servo go out in 727 before and they were able to just change the servo
 
yea it's quiet... no noise
just revs up when I step on it.
Click to expand...


the reason the 727 just needed a servo change and not gears is because the gears were fine and the servo was bad which is not what most people would call a blown tranny. it sounds like its something like that in this case. I had a blown 700 in my rig when i bought it adn 2 and 3rd were completly gone and you could here it big time.
IMO yours gears should be fine if there is no noise because in order for that to be a gear it would have to be completly stripped and if that were the case you would have metal all in your gears and wouldn't be able to go more than half a mile before it blew completly. I'd say it's not shifting into R and your revving it up in N. either way you will probably end up taking her apart. Try getting underneath it and shifting it by hand through all the gears then find R.

Just my 2 cents.....

Peace
 
One thing, I doubt it's your issue since it would probably work even 1 quart low as well, but you are supposed to check it hot and AFTER you run the gear selector through all gears. That will usually suck up more fluid.

Again though, if you are topped off according to dipstick in park/neutral, running through the gears probably won't suck up enough fluid to cause slipping issues.
 
there is no reverse servo, or reverse band for that matter. there is only 1 servo for 2nd and 4th.

its not the gears that break that cause a tranny to go out, its the clutches. reverse uses 2 clutch packs, reverse input and low/reverse.

the only way to be sure what it is, is to pull it apart. it could be as simple as a stuck valve.
 
dirtwarrior17 said:
IMO yours gears should be fine if there is no noise because in order for that to be a gear it would have to be completly stripped and if that were the case you would have metal all in your gears and wouldn't be able to go more than half a mile before it blew completly. I'd say it's not shifting into R and your revving it up in N. either way you will probably end up taking her apart. Try getting underneath it and shifting it by hand through all the gears then find R.

Just my 2 cents.....

Peace
Click to expand...

You should keep your 2 cents out, there really aren't any, "gears" in an automatic transmission...they're all hydraulic.
 
You should keep your 2 cents out, there really aren't any, "gears" in an automatic transmission...they're all hydraulic.
Click to expand...
the gears get engaged hydraulically...

I got one for ya.... if there are no "gears" then why is there filters for metal shavings? where could metal shavings be coming from? hmmmm ...... gears.

I forgot about the reverse clutchpack.
 
There are gears, thats where the ratio comes from. The clutches and bands are what controls it, and they are what goes out in an auto trans, but there are gears.

So, there is hope for this trans? I think I'll pull the cover today.
 
dirtwarrior17 said:
the gears get engaged hydraulically...

I got one for ya.... if there are no "gears" then why is there filters for metal shavings? where could metal shavings be coming from? hmmmm ...... gears.

I forgot about the reverse clutchpack.
Click to expand...
WantedaDodge said:
There are gears, thats where the ratio comes from. The clutches and bands are what controls it, and they are what goes out in an auto trans, but there are gears.

So, there is hope for this trans? I think I'll pull the cover today.
Click to expand...

dodgeboy is on the right track, there is a planetary gear set, and it does determine what gear ratio a particular gear has. but it is not the cause of the metal shavings you see in the fluid. those shavings would be from the clutch packs, more accurately the frictions and steels wearing out in the clutch packs. planetary gears very rarely show significant wear.
 
in addition to TJ's diagnosis, if reverse is gone, the others are nor far behind. low gear and reverse are actually "the strongest" points in the trans, as they run through a pressure booster to boost line pressure and hold the clutch packs and/or bands tighter.
 
I talked to a buddy of mine earlier today, he said he thought the trans was probably on it's last leg and the loss of fluid just pushed it over the edge.

He said he would do the R&R and completely rebuild it with upgraded parts, a towing torque converter and a BIG cooler.
Said he would adjust the Lockup for me as well cause I don't have a clue on these newer trannys.:grin:
 
You must log in or register to reply here.

Latest Posts

Top Bottom