Trans Life Expectance (and rear main seal) question

[rwagoner]

I have a 1999 Silverado 5.3 LT with the towing package (which includes the trans cooler). I don't tow things other than a bike rack ... wanted the package for the cooler.nAbout 230,000 miles.

 

Over the past few years, I've been periodically chasing down an oil leak, and it IS leaking less now after changing the valve cover gaskets, the o-rings on the cam and crank sensors, the oil pressure sending unit, and the oil pan gasket. The trans shop insists that it is the rear main seal that is still leaking... about $800 to replace separately, or a few hundred more than a full trans rebuild. The trans is fine ... for a while I was thinking perhaps I should proactively rebuild the transmission, but that (with the rear main seal) would run about $3300.

 

It is not leaking a lot ... a few drops a day.  Doesn't use any noticeable oil compared with when it didn't leak (maybe one quart between changes). I just hate leaks. THink it might be worth changing the seal ... or am I just wasting money if the trans is toward the end of its life? I notice nothing wrong with the trans, but don't know how long they last.

 

Or just let it leak? 

 

All thoughts are appreciated.

 

[KARNUT]

2 minutes ago, rwagoner said:

I have a 1999 Silverado 5.3 LT with the towing package (which includes the trans cooler). I don't tow things other than a bike rack ... wanted the package for the cooler.nAbout 230,000 miles.

 

Over the past few years, I've been periodically chasing down an oil leak, and it IS leaking less now after changing the valve cover gaskets, the o-rings on the cam and crank sensors, the oil pressure sending unit, and the oil pan gasket. The trans shop insists that it is the rear main seal that is still leaking... about $800 to replace separately, or a few hundred more than a full trans rebuild. The trans is fine ... for a while I was thinking perhaps I should proactively rebuild the transmission, but that (with the rear main seal) would run about $3300.

 

It is not leaking a lot ... a few drops a day.  Doesn't use any noticeable oil compared with when it didn't leak (maybe one quart between changes). I just hate leaks. THink it might be worth changing the seal ... or am I just wasting money if the trans is toward the end of its life? I notice nothing wrong with the trans, but don't know how long they last.

 

Or just let it leak? 

 

All thoughts are appreciated.

 

A couple of drips. Don’t have kids.

[Supreme Pizza]

 

    I would not rebuild the transmission. If it ain't broke, don't fix it.

 

     As for the oil leak, you can use special additives.

 

      Regular oil stop leak additives can damage seals by causing them to swell.

 

       This product does not swell seals. It rejuvenates the seals, bringing them back to the elasticity that they were when they were new. Very good product. I have used it many times on rear seals, and it has worked every time so far.

 

         Another name for the exact same product is AT-205.

 

       Note: this product rejuvenates intact seals, it does not repair seals that are missing pieces or that are torn.

 

      If the seal has bullet holes in it, this product will not help.

 

 

 

 

 

 

Edited January 7, 2022 by Supreme Pizza

[Grumpy Bear]

In a few minutes I found that owners of the 4L60E don't actually know how long one will last. Around 250K people seem to just stop reporting. That said, dad had one in one of his pickups go 700K and sold it to a dealer who used it for about 10 more years as a parts chase truck. If they are serviced and not overheated or beaten like a whelp they see to last a long time. If it's shifting sweet don't take it down just because. IMHO of course. It was opinion you asked for...right?  

[Sharpz]

I have no idea how long the 4l60e will last.  I have not had any problems with them and have put a lot of miles on them, where as I know lots of people who have had to get it replaced with as few as 150k on them.  Currently my daily driver has over 320k on it and shifts fine.  As for the oil leak, a quart in between changes isnt that big of a deal and I wouldnt suggest dropping the tranny just to change the rms.  If you start having problems with the tranny slipping or going out, it will need to come out to either 1) be swapped for a new one/rebuilt one, or 2) for that one to be rebuilt itself.   Once the tranny is out, it is a very easy process to change the rms in your truck.  As long as you have a few basic tools and a torque wrench you could easily do the seal, and no mechanic should be charging you full price to do it either once the tranny is out.  At most for an experienced mechanic once the tranny and torque converter are out, it shouldnt take any more then an hour to remove the rms and replace. It should sit for 24 hours so that the RTV silicon sets up before adding oil (jmo), but its an easy job once the tranny is out.

[Black02Silverado]

It is a gamble but for the seal, I would just replace it.  $800 to just fix it is high.  Around here to have a rear main seal replaced on a 4x4 truck is right around $400.  I'm not a fan of oil additives.  If it is leaking then fix the leak, not band aid it.  Like you already stated, there were other leaks and you took care of them so why not just go all out and have a nice dry engine again?

[dna9656]

I don't believe in using a "mechanic in a can" (think "janitor in a drum"); it's hard for some mechanics to get their head around a chemical that affects the rubber in a seal in such an intelligent way and I'm one of them. I know this: some swear by them and some swear at them. Old school wisdom: for any size V-8 1 quart of oil per 1,000 could be normal... oil has to go down along the valve stems and guides; I bet you can guess where it goes from there. ALL engines burn SOME oil. If you're going between 3000 miles or more between oil changes I'd leave well enough alone. If you have the tools, a place, the time, and something else to drive in the mean time you could change the rear seal but here's the rub: I have read that the main cause for crank shaft seal failure is main bearing wear. As the mains wear the crank falls below it's design "home" because the bearings are bigger due to wear. The crank is going to do a job on that new $8.00 seal. So, if this is true replacing the RMS is temporary at best unless you replace the main bearings on the crank, to do that right you should get the crank inspected, resized if necessary and install the recommended set of bearings. I wouldn't want to remove a heavy thing like a crank on my back much less reinstall it on my back with all those connecting rods right there in the way. I would push the pistons up to get them outta the way but I think for a few drops of oil I'd live and let live.

How long does a Tranny last? Well that depends.... depends on a LOT of variables. does it tow? How much does tow? Ever overheated? the only way most guys find out the answer to that question it's too late. It smells burnt and the color is off. My 2006 $l60E had to be rebuilt at about 100k miles. It had design weaknesses. The rebuild fixed all that and I had it upgraded to a 4l70E (Caddy and super sport cars); it has more clutches but pretty much a 4l60E.

I was interested to read that you replaced the valve cover gaskets, if you had a small block that would go without comment, they all leak at the valve cover but the 5.3 head is way different. I have repl. the oil pressure sending unit because it had a clogged screen in it, they took that out...of the current design.

If you got the money, time, etc AND don't want to buy another vehicle you should maybe think about a replacement tranny and a seal, BUT I don't know anyone that can afford a truck payment for a new truck unless they sign for 8, 10, 12 years... I have always said you can do a LOT of maintenance yourself for the cost of a truck payment. I would like a newER truck but even used trucks with the expected mileage cost in the $30 to$40 k range; personally I think that's insane.

Edited January 7, 2022 by dna9656

[Grumpy Bear]

High Mileage Oils contain?

Intelligent Chemicals to do this job!

BECAUSE? 

 

Dry oils shrink seals and cause leaks...evidently around 75K and evidently often enough to require a product to cure the issues their regular oils cause. 

Question!

Is their use a Band-aid?

 

 

 

[Supreme Pizza]

12 hours ago, dna9656 said:

I don't believe in using a "mechanic in a can" (think "janitor in a drum"); it's hard for some mechanics to get their head around a chemical that affects the rubber in a seal in such an intelligent way and I'm one of them. I know this: some swear by them and some swear at them. Old school wisdom: for any size V-8 1 quart of oil per 1,000 could be normal... oil has to go down along the valve stems and guides; I bet you can guess where it goes from there. ALL engines burn SOME oil. If you're going between 3000 miles or more between oil changes I'd leave well enough alone. If you have the tools, a place, the time, and something else to drive in the mean time you could change the rear seal but here's the rub: I have read that the main cause for crank shaft seal failure is main bearing wear. As the mains wear the crank falls below it's design "home" because the bearings are bigger due to wear. The crank is going to do a job on that new $8.00 seal. So, if this is true replacing the RMS is temporary at best unless you replace the main bearings on the crank, to do that right you should get the crank inspected, resized if necessary and install the recommended set of bearings. I wouldn't want to remove a heavy thing like a crank on my back much less reinstall it on my back with all those connecting rods right there in the way. I would push the pistons up to get them outta the way but I think for a few drops of oil I'd live and let live.

How long does a Tranny last? Well that depends.... depends on a LOT of variables. does it tow? How much does tow? Ever overheated? the only way most guys find out the answer to that question it's too late. It smells burnt and the color is off. My 2006 $l60E had to be rebuilt at about 100k miles. It had design weaknesses. The rebuild fixed all that and I had it upgraded to a 4l70E (Caddy and super sport cars); it has more clutches but pretty much a 4l60E.

I was interested to read that you replaced the valve cover gaskets, if you had a small block that would go without comment, they all leak at the valve cover but the 5.3 head is way different. I have repl. the oil pressure sending unit because it had a clogged screen in it, they took that out...of the current design.

If you got the money, time, etc AND don't want to buy another vehicle you should maybe think about a replacement tranny and a seal, BUT I don't know anyone that can afford a truck payment for a new truck unless they sign for 8, 10, 12 years... I have always said you can do a LOT of maintenance yourself for the cost of a truck payment. I would like a newER truck but even used trucks with the expected mileage cost in the $30 to$40 k range; personally I think that's insane.

 

 

I agree with a lot of that.

 

 

However, there is a specific additive that is worth while.

 

The brand varies, but the product is the same.

 

The product does not "fix" major problems, but it will reverse aging related issues.

 

If your hands are dry and cracked, this additive act as the hand lotion.

 

When a seal drys out, the rubber contracts (shrinks) and the spring can no longer hold the rubber against the moving shaft.

 

This product adds the original elasticity back to the rubber, so the spring can pull the rubber back to where its supposed to be in order to stop fluid loss.

 

If you take an old seal and a new seal and an old "treated" seal, and compare them - then the new seal and the treated seal rubber will feel the same. The old untreated seal will feel hard and brittle.

 

Reference the spring:

 

 

 

 

 

 

 

Edited January 8, 2022 by Supreme Pizza

[dna9656]

But is it effective for ED?