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2007 Ford Sporttrac slams into 2nd gear after Trans Flush

I recently had my Transmission flushed at 90K (beyond the 75k). I had my Struts replaced and Full differential service. They found the Carrier bearing Center Ring was blown out said my truck was fine to drive until the part came in. I drove my truck home and it wasn’t until I put about 20 miles on my truck did my truck start to slam into 2nd gear. It goes gentle if I accelerate slowly and eases with I turn the OD off ( but I only tried a few times). I have tried a few forums and there are so many things that it could be. Everything was fine until I had this servicing and they took my truck apart. On a separate unrealated issue I have a check battery light on, but it is a brand new battery. I had my stereo changed out a year ago and the shop said it was the battery failing (only 1.5yrs old). Just though I would throw that in just in case a COMPUTER issue gets thrown out there. My truck has been running fine before all this SERVICING was performed and I was wondering if anyone has any ideas when I take my truck in tomorrow.

I would question what ATF was used in the flush and did it meet the manufacturers specs. Was this done at the dealers?

If the radio is giving you a battery light, I would suspect it is not grounded properly.

"I would question what ATF was used in the flush and did it meet the manufacturers specs."


Additionally, I would question whether the trans filter was replaced.
After a “power flush” it is entirely possible that some debris from a dirty filter wound up back in the tiny fluid passages of the transmission.


And +1 to VDC.

Yeah, what VDC said too.

This is exactly why that I recommend that you NEVER flush a transmission.

Toilets…yes and radiators…yes but never an automatic transmission.

Toilets…yes, Brakes…yes, Transmissions…no flush but a proper fluid exchange…OK, Radiators…no.


@Tester written by a guy with a flush machine. Lacks credibility with me.


I have a flush machine. Does that mean I have no credibility?

Just because you possess a certain piece of service equipment, doesn’t mean you don’t know what you’re talking about.

And that guy nailed it!


I think it also applies to ANY transmission service and the old wive’s tales pertaining thereto.

@tester In your experience how does a flush do with the filter?

My own version of a flush, without filter service as service and filter was done 30k miles previously, was to disconnect the trans fluid line at the radiator, hose it into a bucket and pour 12 qts of fluid into the trailblazer while the engine is running, as without cracking the housing only 6 qts get changed. I marked the 5 gal bucket quart level to be able to refill matching output.

Surprising to me was fluid did not look bad on the stick, but sure did look bad in the bucket. Get some extra jesus clips i you try this at home.

There are so many myths out there but I agree that a poorly maintained transmission will likely fail, whether or not a flush is done. The flush gets blamed but the reality is that the transmission was not properly maintained and that is what caused the failure. This is equivalent to not changing your oil for 60,000 miles and then blaming the next oil change for your engine failure.

@Tester if you own one of the machines, then you have a vested interest in what you say about it. It does not mean that you are wrong, it just means you are more likely to have a bias. Of course if you were a flush machine salesman, you would be even more biased.


Some transmissions don’t have a serviceable filter.

On this vehicle, the factory service manual directs you to drain the transmission fluid thru the drain plug.

Then remove the pan and replace the filter.

Once the new filter and pan are installed, connect the automated transmission fluid exchange machine between the outlet line and inlet of the transmission cooler.

Run the automated transmission fluid exchange machine until all the transmission fluid has been replaced.

Check the level of the transmission fluid, and test drive the vehicle.


The flush did not cause the transmission problem. The car is 11 years old and from the post that flush was the first time the fluid has ever been touched.

I’d venture to say that a competent, thorough scan and diagnosis will reveal a problem with a pressure switch, servo, etc.

Tester is dead on correct and the link provided says it all.

Everything was fine until I had this servicing and they took my truck apart.

A transmission flush usually doesn’t involve taking the truck apart. In most cases they hook the flushing machine up to the cooling lines is all. BTW, recommendations here are to also drop the pan and replace the transmission filter as part of a flush. Is that what you mean by “they took the truck apart”?

I have a check battery light on, but it is a brand new battery.

That could be a problem with the battery connections or a problem w/the alternator too. Since the transmission problem started immediately after the servicing, and you’d no other electrical problems, I’d discount that as being related. Is this battery warning light still on?

In your last reply, you defended “fluid exchange”. The OP said he/she got a “fluid flush”.

Some mix those two terms loosely. Flush machines can include higher pressure machines and cleaning agents.

If the OP got a “flush” using higher pressure and cleaning agents, are you still supporting that?

If you are, are you saying the risk of debris getting loose and binding a valve in the valve body is nothing to worry about?

I’ve said this before and I will repeat it again. A properly administered transmission flush will probably do no damage. The problem is that most transmission flushes are not properly done. The wrong equipment is used or a bonehead technician with little or no training puts his grubby hands on your vehicle. Flushing can and will damage a transmission if the perfect storm of a qualified technician and proper equipment is not used. Perfect storms are rare so that’s why I recommend never getting a transmission flush. The jury is still out on “fluid exchanges.”

“qualified technician and proper equipment” and proper fluid.