2013 8HP70 Fluid Change or not?

[Chris Capps]

I have to admit that I have been naive about the "lifetime" fluid in the ZF tranny. I am generally a little more on top of things than this. I have a 2013 Longhorn that I replaced the engine in about two years ago at 186K. The truck was in great shape and super clean. I couldn't stomach scrapping it. I went around and around trying to decide on which replacement engine to buy. I went with a brand-new long block with a warranty. All that to say, the tranny seems solid and I literally took the lifetime fluid thing to mean just that. I feel a little stupid. So, now I am thinking I want to change the fluid, but I am nervous. The tranny has about 209K on it now. I have a 1972 Chevy with the original 3-speed automatic in it that I took to have a leak fixed years ago. The guy told me that if the tranny was running well, he wouldn't consider pulling the pan if it were him. That has me wondering if I should even bother with the fluid change on the RAM. Thoughts?

 

[Atcer2018]

I have to admit that I have been naive about the "lifetime" fluid in the ZF tranny. I am generally a little more on top of things than this. I have a 2013 Longhorn that I replaced the engine in about two years ago at 186K. The truck was in great shape and super clean. I couldn't stomach scrapping it. I went around and around trying to decide on which replacement engine to buy. I went with a brand-new long block with a warranty. All that to say, the tranny seems solid and I literally took the lifetime fluid thing to mean just that. I feel a little stupid. So, now I am thinking I want to change the fluid, but I am nervous. The tranny has about 209K on it now. I have a 1972 Chevy with the original 3-speed automatic in it that I took to have a leak fixed years ago. The guy told me that if the tranny was running well, he wouldn't consider pulling the pan if it were him. That has me wondering if I should even bother with the fluid change on the RAM. Thoughts?

This is a tough one. I’ve always heard but never experienced the, “don’t change the fluid” after it gets really old debate. The ZF transmission is a robust unit and at 209k it’s served you well. If it were my vehicle I’d change the fluid and pan/filter with the belief that the transmission is already on borrowed time. Will it fail because of the fluid change? Possibly but isn’t it headed that way anyway? Maybe Wild One will chime in on this as he’s the resident 8HP guru. Maybe several fluid changes within a few hundred miles to really get a lot of the old stuff out. Valvoline MaxLife ATF has a good reputation in the 8HP and it’s way cheaper than the OEM fluid. Run a couple of gallons through the old transmission and hope for the best. Back in 2019 we bought my college bound daughter a 2012 Honda Civic that had 150K miles on it. The seller was the original owner and had records and receipts for every 5K oil change but zero transmission service. Honda is known for great engines but transmissions not so much. On the Civic forums the prevailing opinion was change the fluid four times back to back after a thirty minute drive. Five years later at 259K miles it’s still working although I did have to replace a third gear shift solenoid that was gummed up. Tough call, please keep us advised what you decide and the results.

 

[Wild one]

If it was my truck,i'd do what AT says,but it's not my truck,and to do a new pan/filter and a couple back to back fluid changes isn't going to be cheap.
I've never seen a new filter and new fluid hurt a high milege transmission that's still in decent shape and working good.

 

[EdGs]

If it were mine, I would do a fluid drain and fill once, and then once more with a new pan/filter after a short bit.

I would not do any kind of flush, though.

That way you would have 75% new fluid with a new filter on the 2nd drain and fill.

 

[Chris Capps]

I appreciate the suggestions.