Tandem T-slim

I just started using the Tandem pump. In just shy of one month, the pump malfunctioned. It stopped feeding insulin. I didn’t know what was going on! I tried a new bottle of Humalog, x3 new sites. The battery was draining fast, out of transmitter range alarms. This despite bring inches from the transmitter. I started using my old Medtronics pump, everything went back to normal. Tandem didn’t want to replace the pump given all this info. Further, the pump said it had dispensed 98 units in 6 hours. I would have been dead a few times over. After two days of nonsense, I asked for a return. Being within the window, they had to grant it. Then came the replacement offers. I declined. I told them if I had this much trouble with customer service, forget it. Going back to Medtronics. I will use Dexcom with the pump until their new sensor is available. Just an FYI on very poor customer service.


I know things change, but when I started with Tandem they were nothing less than spectacular with customer service!
Sad to hear that is changing, or at least you experience is definitely less than expected, by far.

The pump, with Control-IQ is still probably the BEST one out right now, as for commercially available closed loop goes anyways.


That’s been my experience as well. Both Tandem and Dexcom’s customer service has always been very willing to help me out with questions and tips.

I can see how this service can degrade as the companies grow. It’s difficult to scale that product knowledge.

The other thing is that this is a complex product and the Dexcom / Tandem setup has plenty of problems - so there’s lots of room for improvement, frustration, disappointment.

But I’d agree with @hammer that this is the best we’ve got right now. Especially with the control-iq.


I was shocked they wouldn’t replace a new pump. Liability alone should have forced it. Two days of tech support, transferrd to higher levels of “tech support” I won’t use their product again. Medtronics is coming out with a Dexcom type sensor. I will be using their products.

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That is definitely unusual for Tandem. I’ve had a great experience with their pumps (going on 4 years) after using Medtronic for over 20 years. I’m never going back. Sorry you didn’t have a good experience.


Sorry you experienced such poor service. I have had great response from Tandem, although some long holds during initial COVID and reps working from home transition.

My endo was also helpful in getting better results by suggesting changes to settings.
I do miss the medtronic quick sets, which I used with 5xx paradigm pumps for 20+ years. But overall prefer the Tandem pump once I got the settings tweaked and “set it and forget it”.


Wow, I’m surprised to hear this! I had above and beyond great service from Tandem, but if I had had your experience, I would have taken the same action based on principle of the matter.


Surprised as well. They replaced mine twice in one year (broken screen, my fault, and then some crazy error that happened occasionally). Both times replaced in 24 hours.

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Well, I’m glad it worked for you. I still can’t believe it. They kept shifting me to higher levels of tech support. 98 units dispensed in 6 hrs! Yet my blood sugar was climbing, I was at 400. Battery draining fast. I didn’t believe it was the pump until I switched back to Medtronics. I changed my site, insulin… custom service didn’t offer a replacement until I asked to return it. That’s terrible service on a brand new pump. The Medtronics and Dexcom are working great. I won’t do business with tandem again. It took two days of phone calls, nothing resolved. Had they sent a replacement, I certainly would still be using it. After the return window is closed, who knows what would happen then. I’m just putting the info out there, just in case others have had issues. Talking to 3 tech support members, not one disputed there was a problem. And still not one of them would send a replacement. Funny thing is, the pump worked great for the first 3 weeks

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Does medtronics work with dexcom?

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I’m using them together, working very well. The new Medtronics 780 will have a “dexcom” type sensor. When the FDA approves it, I’ll switch over to their sensor.


I’m just wondering one thing. Exactly what is a “Dexcom type sensor”? Medtronic has been selling sensors for at least 15 years, and nothing they have sold is anywhere near as good as Dexcom. They have promising better sensors for years, and produce no real improvements.

My first Medtronic sensor, about 15 years ago, was a doorstop. They said something was wrong with my body chemistry, and I would never be able to use a CGM. Luckily for me, someone in the diabetes community suggested I try a Dexcom. They were definitely right! The Dexcom was terrific.

About ten years later, my endo suggested I try the new Medtronic 670G with the new sensors. The pump was good, the closed loop algorithm seemed to work well, but the CGM was still horrible. After all those years, they hadn’t produced a product anywhere near as good as Dexcom. The sensor fed garbage into the algorithm, and the results were poor. I went back to using Dexcoms with the 670G pump and no closed loop.

After four years, my insurance allowed me to get a new pump, and I got a T-slim. Now I use their Control IQ system, and I’m happy with it. After almost 20 years with Medtronic, I doubt I’ll ever use a Medtronic again. Their customer service may be great, but I’m tired of dealing with their CGM’s. I realize that your experience may be different, but I’m happy where I am.


Thanks @Ray and welcome to FUD!


Damn @Voltageman67 that is a rough time. Sorry you had a tough experience with Tandem Tech Support, and understand why you would switch back. Hopefully the new MDT sensor is good, but having a fair amount of experience with them I wouldn’t hold your breath. Their sensor team is a bit behind the times as they say. Might be better to keep working with the Dexcom although I am sure there are some algorithms that would appreciate the info. Too bad MDT never integrated with Dex and gave their patients a choice.

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