Transmission service declined (1 Viewer)

[nodaksn3]

My '99 has 352,945 miles (and never had the transmission serviced!) but before heading back to Arizona from Mass. I thought it might be a good idea to get it done. Trans- Medic in Windham, NH was the recommended place so I called to get an appointment. "Andy" answered the phone and when he found out the mileage of my truck and that I'd never had the tranny serviced he recommended to leave it alone as servicing it might cause more damage than good. Two things: (1) I'm impressed with his honest appraisal, but (2) I've never heard of that before.
Any body else been told that or has anybody encountered a problem of this sort? I plan on keeping this thing for the rest of my life (I'm 79) so should I now be worried about a sudden demo of the tranny "somewhere in Iowa"?
BTW Andy is one of my new heroes and I'm kind of disappointed that I can't give him business!
Thanks, Ned

 

[97 AZ LC]

I've become convinced that transmission "fluid shock" is a real thing. And I think a lot of shops like Andy think it's real. To me the solution is gradual fluid change - like drain a couple of quarts and add back a couple quarts, and do that a couple more times over the next year. But I think I wouldn't do that until I got home. Just take it easy.

 

[dbleon]

The profit from changing you fluid was not worth the liability of something bad happening. Smart businessman.. but maybe not to be taken as gospel. To him.. simply.. the juice not worth the squeeze

 

[rexington14]

That is impressive how many miles are on your transmission without it ever being serviced. What a beast.

I'd probably listen to the mechanic and just keep going. If the transmission dies, it served you well, and at this point with that many miles I don't think you could look back and say a flush or drain and fill would have prevented it. You can always put in a new/rebuilt one if it fails.

 

[94SRUNNER]

I've been told by a Toyota tech that on higher mileage transmissions to just do drain and fills, not flushes. The full flush is not healthy for them as it gets rid of to much of the friction material in the existing fluid. Made sense to me, but I am not a transmission expert.

 

[excessive]

I agree with Andy

 

[Dilspec]

I also agree with Andy. Not worth the risk for you, or him.

 

[bobNoobie]

Drain and fill every oil change every 3 month for a year and your transmission will thank you

 

[NCMTNS]

Having an 04 LX470 with 305k I did a flush around 6-8 months ago @ 290k. Last week started getting torque converter shudder. Based on local independent Toyota mechanics and a couple of transmission shops they all recommend getting tranny rebuilt. I could look at just doing TC but by the time I spend money replacing that could spend a few $ more and get rebuild.

Can’t pinpoint that flush did the damage but probably should have left it alone.

 

[nodaksn3]

Thanks for the answers guys. I'm going to leave it alone.

 

[FamilyCamper]

Having an 04 LX470 with 305k I did a flush around 6-8 months ago @ 290k. Last week started getting torque converter shudder. Based on local independent Toyota mechanics and a couple of transmission shops they all recommend getting tranny rebuilt. I could look at just doing TC but by the time I spend money replacing that could spend a few $ more and get rebuild.

Can’t pinpoint that flush did the damage but probably should have left it alone.

Did you ever get a quote to replace or rebuild? Curious as I have 361k on original. What did the torque converter shudder feel like?

 

[Foehammer]

I was told the same thing by both my dad and my neighbor; lifelong mechanics. Leave well enough alone if transmission hasn't regularly been serviced.

 

[Malleus]

You have to understand how an automatic transmission works, in order to understand whether whether the recommendation never to change the fluid makes sense. This recommendation is as old as automatic transmissions themselves. It's voodoo, and dangerously bad advice. More transmissions fail due to lack of fluid maintenance than any other cause. The fact that there are some (and I have one) with multiple thousands of miles on them is no reason to suspect that dirty fluid is the cause for their longevity. The more likely reason is that they were either built very tightly to begin with, treated very well during their service life, or both.

An automatic transmission works by using a stack of rotating clutch plates alternately sandwiched between a stack of non-rotating steel plates. The friction material on the clutch plates must contact as much surface area on the steels as available (that is, the full width of the plates) in order to provide the clamping force necessary to stop the clutch plates from spinning, and thus engage any particular gear. The less clutch friction material actually adhered to the plates, the less the clamping force. Period.

The purpose of ATF is primarily to enable the separate gear assemblies to function on call. Its secondary purpose is to provide cooling to those clutch plates and steels. ATF provides absolutely no friction benefit. As a matter of fact, loose friction material suspended in ATF actually prevents the clutch plate surfaces form contacting the steels. There simply isn't enough clamping force in the hydraulic system to overcome the mass of suspended particulate, so the clutches slip. Dry clutch systems work all over the world; they don't need ATF. They work because the friction material on the clutches has sufficient grip to grab onto the pressure plates. When they lose enough material, they slip. An automatic transmission works the same way, they substitute hydraulic fluid pressure for a clutch pedal.

There is absolutely no risk of damage to a modern automatic transmission from replacing fouled AT with clean fluid. Worn clutch plate slip, to one degree or other. They can't do anything else, and every clutch plate wears every time it's engaged. That's the way they work. They are supposed to be sacrificial components.

Worn valve body pistons, and their bores, will not be helped by suspended clutch plate friction material in there bores. If this could happen, there would be a huge market for ATF with friction material in it to "restore" failing transmissions. There isn't.

A failing torque converter cannot be hastened to its death by a fluid change. It's a pair of fans sandwiched between a couple of bearings. They fail because they cannot maintain internal pressure and the fans become unbalanced, or simply lose their efficiency.

 

[97 AZ LC]

Having an 04 LX470 with 305k I did a flush around 6-8 months ago @ 290k. Last week started getting torque converter shudder. Based on local independent Toyota mechanics and a couple of transmission shops they all recommend getting tranny rebuilt. I could look at just doing TC but by the time I spend money replacing that could spend a few $ more and get rebuild.

Can’t pinpoint that flush did the damage but probably should have left it alone.

You went 15k miles on the new fluid. Fluid shock happens almost immediately. You also have a very different transmission than the original poster - good transmission, but not as robust as a 1999 A343F 4 speed.

 

[NCMTNS]

Did you ever get a quote to replace or rebuild? Curious as I have 361k on original. What did the torque converter shudder feel like?

I got a few replacement quotes so far but waiting on rebuild option. It's a 3rd vehicle so no big rush. The shudder felt like running over rumble strips on road from around 35mph to 45mph then went away. At first was every now and then but then started happening all the time.

 

[NCMTNS]

You have to understand how an automatic transmission works, in order to understand whether whether the recommendation never to change the fluid makes sense. This recommendation is as old as automatic transmissions themselves. It's voodoo, and dangerously bad advice. More transmissions fail due to lack of fluid maintenance than any other cause. The fact that there are some (and I have one) with multiple thousands of miles on them is no reason to suspect that dirty fluid is the cause for their longevity. The more likely reason is that they were either built very tightly to begin with, treated very well during their service life, or both.

An automatic transmission works by using a stack of rotating clutch plates alternately sandwiched between a stack of non-rotating steel plates. The friction material on the clutch plates must contact as much surface area on the steels as available (that is, the full width of the plates) in order to provide the clamping force necessary to stop the clutch plates from spinning, and thus engage any particular gear. The less clutch friction material actually adhered to the plates, the less the clamping force. Period.

The purpose of ATF is primarily to enable the separate gear assemblies to function on call. Its secondary purpose is to provide cooling to those clutch plates and steels. ATF provides absolutely no friction benefit. As a matter of fact, loose friction material suspended in ATF actually prevents the clutch plate surfaces form contacting the steels. There simply isn't enough clamping force in the hydraulic system to overcome the mass of suspended particulate, so the clutches slip. Dry clutch systems work all over the world; they don't need ATF. They work because the friction material on the clutches has sufficient grip to grab onto the pressure plates. When they lose enough material, they slip. An automatic transmission works the same way, they substitute hydraulic fluid pressure for a clutch pedal.

There is absolutely no risk of damage to a modern automatic transmission from replacing fouled AT with clean fluid. Worn clutch plate slip, to one degree or other. They can't do anything else, and every clutch plate wears every time it's engaged. That's the way they work. They are supposed to be sacrificial components.

Worn valve body pistons, and their bores, will not be helped by suspended clutch plate friction material in there bores. If this could happen, there would be a huge market for ATF with friction material in it to "restore" failing transmissions. There isn't.

A failing torque converter cannot be hastened to its death by a fluid change. It's a pair of fans sandwiched between a couple of bearings. They fail because they cannot maintain internal pressure and the fans become unbalanced, or simply lose their efficiency.

Great info. Thanks.

 

[Tareq]

If this was my 99, I would drain 1 liter only, then fill 1 liter from the dipstick.
Make sure fluid level is correct.
Then do the same every oil change.

 

[Moparsncruisers]

You have to understand how an automatic transmission works, in order to understand whether whether the recommendation never to change the fluid makes sense. This recommendation is as old as automatic transmissions themselves. It's voodoo, and dangerously bad advice. More transmissions fail due to lack of fluid maintenance than any other cause. The fact that there are some (and I have one) with multiple thousands of miles on them is no reason to suspect that dirty fluid is the cause for their longevity. The more likely reason is that they were either built very tightly to begin with, treated very well during their service life, or both.

An automatic transmission works by using a stack of rotating clutch plates alternately sandwiched between a stack of non-rotating steel plates. The friction material on the clutch plates must contact as much surface area on the steels as available (that is, the full width of the plates) in order to provide the clamping force necessary to stop the clutch plates from spinning, and thus engage any particular gear. The less clutch friction material actually adhered to the plates, the less the clamping force. Period.

The purpose of ATF is primarily to enable the separate gear assemblies to function on call. Its secondary purpose is to provide cooling to those clutch plates and steels. ATF provides absolutely no friction benefit. As a matter of fact, loose friction material suspended in ATF actually prevents the clutch plate surfaces form contacting the steels. There simply isn't enough clamping force in the hydraulic system to overcome the mass of suspended particulate, so the clutches slip. Dry clutch systems work all over the world; they don't need ATF. They work because the friction material on the clutches has sufficient grip to grab onto the pressure plates. When they lose enough material, they slip. An automatic transmission works the same way, they substitute hydraulic fluid pressure for a clutch pedal.

There is absolutely no risk of damage to a modern automatic transmission from replacing fouled AT with clean fluid. Worn clutch plate slip, to one degree or other. They can't do anything else, and every clutch plate wears every time it's engaged. That's the way they work. They are supposed to be sacrificial components.

Worn valve body pistons, and their bores, will not be helped by suspended clutch plate friction material in there bores. If this could happen, there would be a huge market for ATF with friction material in it to "restore" failing transmissions. There isn't.

A failing torque converter cannot be hastened to its death by a fluid change. It's a pair of fans sandwiched between a couple of bearings. They fail because they cannot maintain internal pressure and the fans become unbalanced, or simply lose their efficiency.

But doesn't ford Type-F have "friction material" or something of the like in the fluid? That was always the go-to in nostalgic drag racing, for more "bite" ...

 

[baltistyle]

I replaced fluid in a 250k mile truck that likely was never done and didn’t think twice. I replaced three quarts at a time over two weeks. Make sure to use the right fluid. The truck has not skipped a beat. A worn transmission is worn regardless of the fluid. A power flush pushing debris in the wrong direction is never recommended. I’ve never had an issue at any mileage on any vehicle when servicing fluid. There is no such thing as lifetime fluid, unless it means that you replace the fluid when you replace the prematurely worn part due to having not changed the fluids sooner. Op, just do it slowly and you’ll be fine, imho. I understand the mechanic you went to didn’t want to do a full fluid exchange but that should not prevent you from changing the fluid yourself slowly and over time.

 

[Malleus]

I use the transmission pump to change the fluid; disconnect the cooler and use the supply line for a drain. That way, all the fluid gets replaced at once and the system is as clean as can be, without opening it.

If it's safe for operation, it's safe for maintenance.