1993 4cy Leaking Transmission Fluid Is this from my differential cover?
 

I had my transmission rebuilt about 2 years ago. I have put about 30,000 miles on it. Last week it started streaming out transmission fluid. When I pulled into my garage smoke was pouring out. It was dripping on the exhaust. It started leaking about 3 blocks from my house.


Oil starts streaming out after about 30 seconds from starting the car.


I showed the pictures to the guy who rebuilt it, and he said that it is leaking from the Differential cover. Which I guess he never touched.


I just wanted to know if he is correct, and how big of a job is this to fix the leak. Can it be done without removing the transmission?




Thanks

Auto or manual?

Is this the cover or the small nib (whatever it is) under the cover?

If the cover can be be removed on the car, then it can be fixed without taking out the trans.

Sorry, this is an Automatic transmission. Not sure what you mean by nib....


Thanks

Is the fluid leaking out from the gasket on the cover or some other location. If the cover, it can be removed IF you have enough tool access then the gasket replaced. The cover is just that, it supports or holds nothing but allows access to the gearing.

Well I got a better look this morning with my camcorder.

https://flic.kr/p/nwn5v3

It defiantly is not from the differential. This is where the transmission connects to the engine. It appears to be up inside the transmission. Total fail. :(

Make sure the fluid is transmission and not engine oil. The crankshaft has a seal in the area.

If trans fluid and leaking out the bottom of the trans bell housing where it bolts to the trans, the trans input shaft/oil pump seal may have blown. This seal is under fluid pressure and if bad can have a major leak.

If the leaking seal is the only issue (trans still works OK), the seal can be replaced from outside the trans housing much like a crankshaft seal. The trans will need to be detached from the engine to access the seal.

Oh yea its for sure Transmission fluid. The transmission still works great.

Well that will be good if this can be fixed without having to remove the transmission, because removal is a big job on this car. I paid $400 last time to have it removed and installed.

Thanks.

The oil leak location is different from what was assumed in the first post. It is not the side cover of the trans but the input shaft seal. The shaft inserts into the torque converter inside the bell housing.

The only way to access the seal is to remove the trans, then torque converter.

Suppose could also be a leak in the torque converter but this rare.

You need to remove the trans to remove the converter and gain access. This is time consuming as the front axles need to be removed also.

What repairs did you have when the trans was last removed?

The guy did a full rebuild. Torque converter was also replaced. Last time the bearing on the overdrive cover failed, and parts went into the trans and messed up the reverse (Slipping). So had to rebuild and replace the overdrive cover.

Obviously something failed, can only speculate. This would be the trans input shaft/trans oil pump seal, torque converter seal or rarely a leaky converter body.

The torque converter is filled with trans fluid.

This repair have a warranty, if so suggest following up. If a proper rebuild, these parts should have been replaced and you stated the converter was replaced. This kind leak is uncommon and much more so given the large flow of oil.

How long ago was this rebuild?

Suppose it is possible the converter was re-installed improperly leading to the issue, but only a guess.

The link below has photos of the trans input shaft/oil pump seal and other trans seals. To access these seals requires removing the trans.

https://www.google.com/search?q=torq...ml%3B800%3B600

Review the top row of photos. The third photo from the left has fluid leaking out under the input shaft, a bad seal.

Once the trans is out, repairs should be straight forward.

Thanks for the link to the photos. Makes sense it would be coming from that seal. Yea unfortunately I had it rebuilt 8/2011, I got 39,000 miles out of it already. I'm guessing if the torque converter was not installed correctly it would have failed sooner no? The guy I had remove and install my transmission in my opinion a very talented mechanic. He mainly works on performance mustangs. But he knows his stuff. I have heard nothing but good things about him.


Thanks.

As the cause of the leak is unknown, can't state the torque converter was installed improperly. Just that this leak is not common and more so given the low miles since rebuild. As such looking at how rebuilt, parts used, how installed, etc. Suppose possible to have a defective torque converter.

Although frustrating, assuming nothing unusual the repairs should be straight forward. Perhaps you know someone needing extra cash that can remove/install the trans cheaper. Then once out, take it back to the rebuilder for inspection and repairs. Which given how unusual the leak, they may do at a low cost.

I cannot get a hold of the guy who removed my transmission. He may be out of town. My dads truck that he bought used, it's transmission blew up like 4 months after he bought it. He contacted the guy who rebuilt his, and he said he will do the job for $400. So I'm going to have him do it. So he will be able to inspect and figure out what happened. Now I don't have to haul my transmission around. I think $400 is a good deal. For sure cheaper then another used car. Last year I did the Water Pump, Timing Belt, Oil Pump cover seal myself. Engine runs great.


ALSO, I should have thought about this last time. But isn't their a REAR oil seal on my engine in the area from where the transmission is removed?


I'm wondering if I should have the guy replace that seal this time?


Thanks

$400 is a good price. Unless a converter issue or some other unknown, parts and repairs should be low cost.

As to the rear engine seal, leakage is rare but does happen. With trans out the replacement is easy as same type of seal as the ones you replaced, plus a low cost part. Yes, ask that the rear engine seal be replaced.

When all accomplished please post back with the results. Curious as to what part failed in the trans.

I had my car towed to the mechanic last night. I talked to him this morning about the rear seal. He said he will make sure its good, but doesn't recommend changing it unless its going bad. He says they rarely fail. Just like seal on trans rarely fails right? hahah. Maybe its one of those things that if it isn't broken don't try to fix it......


I'll let you guys know as soon as I hear back from him as to what failed on my transmission.


Thanks

Mechanic just called. Says I need a new Torque converter and Transmission oil pump. He said my rear engine seal is leaking a little, so he is going to change that out. So now looking at around $800-$850 parts & labor :(... I guess its better then buying another used car which could also have problems down the road to fix. Hopefully after this I'll get another 100K out of it.


So not sure what really caused the failure, not installed properly, I don't think Pump was replaced last time. So either pump caused the problem or Torque converter, he said something like they were rubbing against each other. I got second hand information because my dad is the one that talked to him. So when I go to pick it up I'll get the full details.

Is this the same mechanic who rebuilt the trans or someone else?

Without seeing parts, can only guess. Perhaps after repairs your Dad can retrieve parts and you take pictures.

A bad pump would cause transmission operational issues as there would be low fluid pressure which is different from a leaking seal.

Suppose the pump bearings could fail or torque converter have to much run out.

Ask you Dad if any conversations of a cracked or bent flex plate. This is the plate that bolts to the crankshaft then torque converter. If cracked or bent, it could wobble too much and cause rubbing or parts. The flex plate replaces the flywheel that cars having manual transmission use.

Might also ask the shop to remove the trans pan, clean it plus replace the filter screen.

I have a different mechanic working on my car now. The previous one rebuilt my dads van and my friends ford truck. Both of them had problems after rebuild. Mine was the only one working correctly. So he is now FIRED!

His response to my problem was have my guy remove the transmission and then he can take a look at it. He said he has no time to remove it. Umm ok. So not doing that again having to haul my transmission around then car has to sit it the persons shop waiting.

My car will probably be done this afternoon if he has all the parts.

I told my dad to have him save my old parts so I can take pictures. Either way I like to see OLD parts you know to make sure they were really replaced. ;)

I think the pump probably still works, but now it is the cause of the leak. I remember my dad saying something wore, like maybe the Torque converter was wearing out something on the pump and then it started leaking?

Thanks for posting back. Curious also in just what failed.

Ok here are the pictures of the Failure. He can't say 100% of what caused the failure. Either bad install or I got a bad torque converter. Curious what thoughts anyone has based on the pictures.


Because of the rubbing it wore the bushing on the Pump, that is why they had to be replaced the pump.


The mechanic also didn't like the transmission fluid that was in there, he said it seemed watery compared to what he normally uses or sees. Fluid was replaced in both differential and transmission.


He test drove it on the highway. Says the car runs great. Transmission good again. He didn't see any leaking, before the major leak it was also leaking somewhere around the differential (after rebuild).


So now I shouldn't see anymore MOTOR oil or trans fluid in my garage :):) I'm glad I got that engine rear seal replaced. Because after I fixed the engine oil pump cover seal I was still seeing a little oil dripping. I'm sure it was the rear seal.


Total was $400 Labor, and $381+tax parts.

Great pictures!

If wear on the hub (pipe sticking up) is not uniform all the way around, might be an alignment issue or hub not centered on torque converter due to manufacturing error.

The second mechanic should see this and have taken any steps required to solve the issue.

Watery fluid is in thin fluid?

Might change all trans fluid in 40K miles. Cheap insurance.

Even though this problem should not have happened, the repair cost was OK. Most trans shops would have insisted on another rebuild or exchange to make extra profit.

Thanks for posting back with the photos and repairs.

Thank you, Umdaman for posting great pics of the worn out parts. This thread has been really informative and I'm glad you're back on the road!

I hope that it was just the MFG of torque converter and not something else wrong that is going to wear out my new one. In regards to the fluid, he said it seemed thin. So he changed out the fluid. But I will change fluid again around 40k, I think that is the normal time to change fluid if I'm not mistaken... I know a lot of people completely forget about their fluid in the transmission also gets worn out.......


I'm guessing the 2nd mechanic would make sure everything is aligned on this one. Good thing this 2nd guy is a brother-in-law of guy my dad knows very well. So that is a reason why I was not charged thousands. But yes I'm sure others would just say you need a new transmission. Just like the last mechanic that estimated $950 to fix my wife's Oil pump cover seal. They had in the quote for a NEW OIL PUMP also added in new water pump even though it was changed about 20k miles ago from previous owner... Yea umm ok. So I just changed the Oil pump cover gasket for like $8 or something like that. It's a 2000 but pretty much same engine so after doing my timing belt work this was a piece of cake job for me. After finding this leak I then knew that mine has the same leak because it has never been changed! So I did mine right after that one hers was major leak too mine was just slow leak.


Your welcome for the photo's. Hopefully someone else will find this thread useful if they ever have similar problems.


It sure is embarrassing when you have to have a Toyota towed away.. LOL.
I almost have 197,000 Miles on this bad dog . I'm hoping for another 100k!

Just wanted to add. I asked the guy who rebuilt my transmission, if he had an idea of what could have caused this. This was his response:

When the torque converter was installed the attaching bolts were not tightened in increments going around the diameter of the torque converter, rather the first bolt was tightened, then the next bolt was tightened, and so on. What happens is that when the trans is installed the weight of the torque converter is being supported by the pump bushing. If the torque converter isn’t rotated a couple of times, and then wiggled back-and-forth once all bolts are in place while the bolts are being incrementally tightened, the torque converter becomes joined to the flywheel in the undesirable posture. Lucky the flywheel didn’t crack.
Replacing the torque converter in addition to the bushing/seal is certainly the highest quality repair.

When I install a trans and use my technique I have noticed that upon later disassembly that the torque converter hub barely touches the bushing. Rather acts as a guide, not a support.

Sounds like that makes sense. I tend to do that circular tighten a little bit and then move onto the next bolt and slowly work my way around thing in any application that it can be done.

Thanks for posting with this information.