Should I service a '97 4l60E at 167k? Leave alone?

[HawkeyeScott]

I just picked up a cheap 3rd rig for mountain and fishing use. It's a 1997 GMC Yukon that's lived its entire life in the high desert. It came from the family that bought it new. It had 105k miles in its first 9 years, then only 60k over the last 13. It hasn't been used to tow anything more than a pop-up, the seller says, and doesn't appear to have been abused. (It was still being garaged.)

The owner says he did a tranny pan drop and put a new filter on about 5k miles ago. I don't have a clear indication of what kind of ATF service he'd done prior to that, if any. The ATF looks pretty good and still has a pretty strong additive smell to it. For a truck with 167k miles, it seems to shift pretty well.

As I go through it with things like fuel filter, brakes, PCV valve, gear oil, etc., I'm wondering if I should do anything to the transmission. My usual move with a new-to-me used vehicle is to drop the pan, install a new filter, add a drain plug and do a few drain/fills until the fluid looks like new. I look at it as a pretty cheap way to add life to the car. That said, I've also heard stories about opening a can of worms when adding new fluid to an older transmission.

Any advice? What would you do?

For those saying drop the pan, what fluid would you recommend? MaxLife? Dexron III? Dexron VI?

Thanks a lot.

 

[Snagglefoot]

If you like you can use a 3/8 " OD plastic tube down the dipstick tube and pull out about a few quarts of ATF and replace it with new ATF. I use a Flo N Go system that uses my shop vac. You can replace it with Dex III which is usually sold as Dex/Merc if you want to be conservative. Repeat every once in a while until the fluid looks fresh.

 

[WyrTwister]

I have used one of these on our 2006 Buick Lacrosse 3.8i to pull 4 quarts from the pan , via the dip stick . Do that a few times . Quick , easy , cheap ( can catch it on sale for $ 5 ) way of doing it . ( Of course , does not get the filter changed out , just fluid . )

https://www.harborfreight.com/multi-use-transfer-pump-63144.html

I look at it kind of like paying for insurance .

 

[HawkeyeScott]

Thanks a lot. Good ideas. And I do have a Topsider, which works pretty well, especially with warm fluids.

I guess my question is more about the introduction of new fluid and if it's worth the risk of upsetting this transmission.

 

[Urshurak776]

Never had good luck with these 4160's. I could get 120K out of them, then fail. Every time. I used fancy dancy Amsoil stuff, after re-build, used nothing but OEM, failed again, then used Max-life, failed again. I didn't tow either. Just occasional lumber from Lowes/HD. Maintenance always done on time, new filters, etc.

Just bad luck on mine. Most people have no issues with them though. My suggestion, just use any fluid that meets spec. Didn't make a lick of difference in my case.

 

[loneryder]

It's already had new fluid at least once so I wouldn't worry about it. Change the fluid and filter. That fluid and filter has approx. 60k miles on it.

 

[andyd]

When I baselined a new to me used car, I always dropped the transmission pan just 'cuz. I once revived a 727 torque flite by changing out a clogged filter and replacing the ATF. Ran like new afterward. Usually if a drain/fill/filter doesn't fix a trans, it was dead already. Yeah yeah, my cousin's aunt's ex-BIL's kid said that some times when you drain the ATF all the ground up clutches and steels that is in solution is providing grip, goes away and trans slips. I haven't had that ever happen.

 

[dave1251]

I would just use your vac and fill once a year or two with DEX VI or Maxlife.

 

[demarpaint]

Originally Posted by andyd
When I baselined a new to me used car, I always dropped the transmission pan just 'cuz. I once revived a 727 torque flite by changing out a clogged filter and replacing the ATF. Ran like new afterward. Usually if a drain/fill/filter doesn't fix a trans, it was dead already. Yeah yeah, my cousin's aunt's ex-BIL's kid said that some times when you drain the ATF all the ground up clutches and steels that is in solution is providing grip, goes away and trans slips. I haven't had that ever happen.

I agree if it grenades it was on its way out anyway. I'd do a fluid change and pan drop. Then possibly a line off exchange of fluid a few weeks later, or a fluid extraction via the dipstick. Over the years I brought a few transmissions for friends back to life doing that. The filters were starting to clog, the new fluid/filter improved the transmission operation considerably.

 

[Donald]

I think its more likely that people only bring their car to a transmission shop when the transmission is half dead. They want a flush to fix it. The shop doesn't want anything to do with the vehicle if they cannot properly diagnose the problem so the shop says he won't flush the transmission. The vehicle owner somehow translates that to you should not flush high mileage transmissions.

 

[dave1251]

Originally Posted by Donald
I think its more likely that people only bring their car to a transmission shop when the transmission is half dead. They want a flush to fix it. The shop doesn't want anything to do with the vehicle if they cannot properly diagnose the problem so the shop says he won't flush the transmission. The vehicle owner somehow translates that to you should not flush high mileage transmissions.



My BIL took his Caravan once upon a time to a mechanic to rebuild his failed transmission. The mechanics assumption is my BIL is not very bright because it had fresh ATF and this is why it failed. My BIL knew it was on the way out and he hoped fresh ATF would buy a few more months. When it didn't he was not surprised. At least my BIL is more reasonable then the mechanic he choose.

 

[RonRonnster]

I have 160k on my ‘98 4L60e which is original to the truck and hasn't been rebuilt yet. I did a pan drop/filter about 5k miles ago and replaced with Maxlife ATF. I would recommend Maxlife ATF - it can usually be purchased at a good price point.

I haven't found the introduction of new fluid to hose a transmission. Avoid a flush, like has been mentioned, and opt for a drain and refill. I've done this several times on my older GM transmissions and have had good success.

 

[supton]

I'm a believer in flushing. You wouldn't leave old motor oil in an engine--so I believe in the same for the transmission. Good oil never hurt anything (well as long as it met spec and all).

Whatever "flushing" machines that were evil and did bad things seem to have stopped existing--no one can name one, yet we're all supposed to avoid flushing. IMO a full fluid exchange is a flush, as opposed to a drain and fill (where only a fraction is removed). D&F is fine (in my uneducated opinion) when the oil coming out is still in good shape; it's main reason to doing that instead of a full drain is that it's easy and fast, and "good enough" to top off additives.

 

[Snagglefoot]

The shop gets a nice fee for doing the flush compared with a pan drop. If you are refreshing your fluid as you go, a simple pan drop with a new filter and magnet cleanup ( if it has one) is usually enough. I've seen tranny filters cut apart that had almost no particles in them. YRMV.

 

[danthaman1980]

Leave it alone. It just had a pan drop/new filter/fluid. As long as he used any Dex III/VI fluid, it should be fine for a long time.

If it ain't broke...

 

[bullwinkle]

Originally Posted by Urshurak776
Never had good luck with these 4160's. I could get 120K out of them, then fail. Every time. I used fancy dancy Amsoil stuff, after re-build, used nothing but OEM, failed again, then used Max-life, failed again. I didn't tow either. Just occasional lumber from Lowes/HD. Maintenance always done on time, new filters, etc.

Just bad luck on mine. Most people have no issues with them though. My suggestion, just use any fluid that meets spec. Didn't make a lick of difference in my case.
They had mods that would allow them to be halfway decent-Corvette servo, extra clutches, etc.-but, never, EVER tow ANYTHING in O/D-that will kill them faster than anything. My brother found out with his Yukon-converter must have failed to lock, blew out all the fluid, trans toasted!

 

[Oro_O]

Quote
I guess my question is more about the introduction of new fluid and if it's worth the risk of upsetting this transmission.


Of course it's worth having good, clean fluid in there.

If it was serviced 5k ago, then I'd pump out the pan (I have that cheap HF pump linked above, works great) and refill. Then repeat every 20 or 25k when you notice it shift a little sloppier. I've seen just a single drain/fill on high-mileage one of these work wonders for the shifting. The earliest models (up to 97) had some weaker internals, TC, etc. 98 on were much better, so take care of this one and don't abuse it and it'll be fine.

 

[stroked93]

leave it alone at this point. Usually folks are looking at their fluid at this kind of mileage because of performance issues related to the transmission. It will continue to get worse and perhaps at an accelerated rate if you choose to change the fluid.

 

[pb]

2004 astro awd, 6 years and 134k miles, I believe there was a rubble/ shudder issue but could have been transfer case. I dropped the pan and filter. refilled with amsoil ATF. no improvement.
2k miles later added lucas trans fix. got worse. lost 2nd gear
transmission was replaced 400 miles later.

 

[slacktide_bitog]

The problem is that GM is too stupid to include a drain plug with the transmission. The good news is that you can get an aftermarket pan that has one