Case Study: Toyota Tacoma A750 Transmission Service Fix

  Case Study Toyota Tacoma Transmission Problems | Toyota Tacoma A750 Transmission Service Repair
  Dave Riccio, Owner/Technician

By Dave Riccio, ASE Certified Technician, Owner of Tri-City Transmission & Auto Repair, Co-host of Bumper to Bumper Radio

CASE STUDY: Toyota Tacoma Transmission

Why Good Transmission Service is SO IMPORTANT!!

A750

This customer owns a model year 2011 Toyota Tacoma 4 Wheel Drive Pickup with 136,233 miles. His truck started getting the transmission shakes or road strip vibration when the transmission would shift. There was also a considerable whining noise that seemed to be coming from the transmission. With a little internet research, he suspected he needed a transmission. What he was finding didn't sound cheap. His eyes where big like beach balls considering he was facing an expensive transmission replacement. At first blush, my guess, not having diagnosed the transmission, a whining transmission pump and negative transmission symptoms in many cases can mean a major transmission repair. We've seen it many times, but experience shows to always go down our extensive diagnostic checklist. Off the cuff answers can often be incorrect, so we don't make them as we don't like to be wrong.

A situation like this is when a well-intentioned mechanic, not knowing any better, condemns a transmission and sends a customer into the Gauntlet of phone pricing to pick what he thinks is the best shop to replace his transmission. What this customer doesn't know is that because he already suspected he needed a transmission, which he suggested to the first mechanic that checked it out, he steered the diagnosis. Unfortunately, well intentioned automotive generalist mechanics who don't know what they don't know about transmissions often give bad advice about transmissions. Customers are their own worst enemy when it comes to this and they get their expectations fulfilled of having a bad transmission - even if they don't need one.

Case Study Toyota Tacoma Transmission Problems | Toyota Tacoma A750 Transmission Service Repair

Fortunately since he already knew of us, when this customer called us for a price on a transmission we insisted he have the transmission truly diagnosed. He said he already did and his mechanic told him he needed a transmission. We corrected him, no, he needed his transmission diagnosed by a seasoned specialist with his best intentions in mind. The customer took heed and dropped his car off for our thorough transmission evaluation. Again, without diagnostic steps, a transmission with a whine and chatter during shifting would indicate a failing transmission. However, in this instance, the whining noise wasn't the transmission at all. It was a failed idler pulley bearing that sounded just like it was coming from the transmission. A stethoscope inspection proved this. Secondly, when we took a fluid sample to our lab it was evident that although the transmission fluid was light black it did not have any evidence that the transmission was failing. The fluid wasn't burnt, nor had any failure particulates or any glycol contamination. It simply had an additive package that was well worn out. The fluid had gone flat like an open can of soda after a week.

We were able to deflate the customer's beach ball sized eyes when we called recommending a transmission service with complete fluid exchange and an idler pulley. Yes, we fixed his supposed transmission problem for the cost of his car payment. He was without his car for two days. He was lucky he heeded our warning and allowed us the time it took for a good transmission diagnostic - not the free type diagnostic where you wait in the lobby. A free diagnostic is often times worth what you pay for it - absolutely nothing. It takes time to run fluid samples, pressure tests and perform multiple test drives to analyze computer data. In this instance this transmission was diagnosed without ever putting a wrench on it, other than the wrench for the drain plug to get a fluid sample and hook up a pressure test tool. It should be noted that most mechanics don't even own a gauge to test transmission pressures. So how do they diagnose transmissions?

I chose this week’s case study for two reasons. We fixed two Toyotas this week with a transmission service. It is rare that we do fix a transmission with a service, however Toyota is an offender as Toyota barely recommends transmission service for what appears to us to be some new car marketing agenda or they just don't trust the competency of the automotive industry to properly service a transmission. I speculate more for the second, because when I interview other shops about how they service transmissions, the responses are all over the map and most are doing it wrong. The biggest offender is the wrong fluid! 90% if not more of the shops I interview use the wrong fluid. This includes some new car dealers and transmission shops alike. These are friends, competitors and colleagues that we socialize with in the automotive repair industry. These friends have bought into the marketing of their oil supplier who swears by "Fits All Oils". My friends have drank that Kool-Aid! It’s way easier to believe the oil supplier's story then to stock 31 flavors of transmission fluid. Last I checked, we stock north of 40 transmission fluids in order to service vehicles properly. The list is still growing.


Consumer Takeaway:

A bad transmission service is worse than no transmission service at all. However, good transmission service is very important just the way it was for this customer's transmission. Consumers, PLEASE, PLEASE, don't just assume your transmission is bad because you might end up getting a transmission you didn't need. I have met customers and technicians alike who swore beyond a shadow of a doubt that their transmission was obviously bad. It is so fun for us save the customer money by not replacing a transmission unnecessarily. We have seen customers do this to themselves for years and have found a true transmission diagnosis is a rare thing. This is the reason why 1 in 3 transmissions are replaced in error.

Word of Caution: It should be noted that just because you’re at the dealer doesn't mean you’re safe or working with qualified transmission technicians. I am sure they have good technicians, however over the last couple decades we have seen dealerships with varying amounts of transmission advice. We believe this is due to the fact that dealerships have gotten out of the transmission business in relation to repairing transmissions - they more commonly just replace them. They are no longer privy to the inside of the transmission and the points of failure. That knowledge level is gone from the dealers and the manufacturers are ok with it. I think because it’s tough to teach transmission as the level of competent technicians who can learn the skill is fading. Because of this, they don't see how much bad transmission service or lack of transmission service can wipe out a perfectly good transmission. NO transmission service or a bad transmission service kills a transmission slowly.

This type of chatter is a daily occurrence at Tri-City Transmission and Auto Repair. This is especially true when it comes to Toyota transmissions. We find Toyota transmissions to be an industry leader. They do fail, just not as often as the rest. We have seen a Toyota transmission with great service records go in excess of 300,000 miles before failing. Believe me, you want to be on that side of transmission life expectancy. We regularly service 10-15 transmission every week. We have our system down and we use quality and experienced transmission technicians - not bottom of the totem pole general repair apprentices most others use.


Transmission Background Information:

Transmission service intervals have changed. In our 45+ years in business, it has come up from every 12 months and 12,000 miles to every 30,000 to 50,000 miles depending on driver habits, region and application. Towing vehicles tend to be at the bottom of the range. We consider a lot of data when making generalized transmission service recommendations. This is why recommendations have changed. Transmission fluids have gotten so much better, on the flipside, transmission controls and the number of speeds have become much more active. The biggest area we see failures are in the valve body. With transmission control as busy as it is, it wears out the valve body, which is the hydraulic brain of the transmission. So, while fluids have gotten much better, transmission needs for good fluid have increased.

Other versions of this transmission are found in many Lexus vehicles and many of the other Toyota vehicles.

A750E - the E denotes 2WD
5 Speed Automatic Transmission (4x2)
Applications (calendar years):
2005-2009 Toyota 4Runner (BA bell housing), 2005- Toyota Tacoma (V6), 2007-2011 Toyota FJ Cruiser, 2005-2009 Toyota Tundra, 2004-2009 Toyota Sequoia.

A750F - the F denotes 2WD
5 Speed Automatic Transmission (4x4)
Applications (calendar years):
2003- 2004 Toyota 4Runner (4x4), 2005-2015 Toyota Tacoma (V6 4x4), 2005-2009 Toyota Tundra (4x4), 2004-2009 Toyota Sequoia (4x4), 2007- Toyota FJ Cruiser (4x4), 2009 Toyota FJ Cruiser (Canada V6 4x4), 2003-2007 Toyota Land Cruiser 100-series (4x4), 2003-2009 Lexus GX 470 (4x4), 2003-2007 Lexus LX 470 (4x4), 2005- Toyota Land Cruiser Prado (4x4), 2005- Toyota Fortuner 4.0L, 2005- Toyota Hilux 4x4 (European Version Only)

Ratio Ranges: 1st gear = 3.52, 2nd gear = 2.042, 3rd Gear = 1.4, 4th Gear = 1, 5th Gear = .716, Reverse = 3.22, Final Drive = 3.583


Click here to listen to Dave Riccio discuss transmission service in detail on the Bumper to Bumper Radio Show


Case Study Toyota Tacoma Transmission Problems | Toyota Tacoma A750 Transmission Service Repair