Life with my Mahindra Thar diesel AT: 2 years & 42000 kms later

I have been using the Thar in city traffic exclusively and continuously for about 2,000 KM in Coimbatore, and 1,000 KM in Hyderabad. Never faced a manual regen situation.

BHPian ph0n!x recently shared this with other enthusiasts.

42,000 KM in 2 years. That is about 15,000 KM from when I started planning for mega updates to this thread, procrastinated, changed jobs, procrastinated, started shuttling between cities, and procrastinated some more.

So guess now is as good a time as any - though I won't be doing mega updates (procrastinate more!). Will make a few mini-updates, covering my life with the Thar for 41,960 KM in exactly two years.

Let me start with the financials - fuel, cost of ownership, stuff that I hope my wife never reads.

Mileage:

  • The lifetime average is 11.99 KMPL
  • My usage is 67.2% Highways, 27.1% City and 5.7% Off-roads (that is a measly ~2,500 KM off the paved roads on a vehicle meant for exactly that.
  • Worst mileage is 9.84 KMPL when most of that tank went into 4x4, best mileage is 14.09 KMPL
  • Cost per Liter of fuel has been ₹91.54 per liter weighted - I have been feeding the jeep with ₹3,15,584 worth of Diesel so far, at the rate of ₹7.63 per KM!
  • Reliance (28% of refills), IOC (26.5%), Shell (23%) and HP (15%) are where I have been tanking up. But with the recent disparity in fuel prices, Reliance and Shell have dropped out, and BP has added 7.5% to its account.
  • I am not reporting mileage-by-brand, as this will be extremely skewed. Thar's mileage will vary if I am driving on this side of 90 KMPH or not, and it does not do justice to the brands. That said, my observation is all of them are on par under similar driving conditions.
  • The MID is, on an average, 1.52 KMPL optimistic! If your Thar's MID says you are getting 12.5 KMPL, you are getting somewhere around 11 KMPL
  • The MID will not go below 7 KMPL. So if you are on a poor-mileage-spiel <cough, cough, mStallions> and your MID is saying 7 KMPL, do not bet your tank range or DTE based on that!
  • The best tank range I have gotten is 740 KM.

If you have been following my mileage reports from earlier (here, here and here), my mileage has been increasing from 11.55 KMPL to 11.61 KMPL to 11.93 KMPL, and 11.99 KMPL being the current. While I have not bothered much about the mileage, what makes the beast more efficient can be summarized in 2 words.

Cruise control:

The best mileages I have clocked have invariably been using/ over-using/ abusing cruise control:

This is from a recent travel between Hyderabad and Madras, where I set a GPS speed of 99 KMPH in the ORR, and 90 KMPH rest of the highways. The average speed for this trip was 76 KMPH, and I ended up with my best mileage of 14.09 KMPL after crawling through peak Madras traffic - MID was 15.4 at the end of the ordeal.

Overall spends:

Right, with that done, let me look at the other expenditures:

Insurance:

  • Own-damage insurance for 2nd year came to ₹ 31,007 (ICICI) for an IDV of ₹ 12,31,912 - coverage includes Consumables, Engine Protect Plus, Return to Invoice, Key Protect, RSA, Zero Depreciation, Tyre Protect.
  • For the 3rd Year (current), I paid ₹ 22,255 (Tata AIG) for an IDV of ₹ 12,00,000, covering Consumables, Engine & Gear box protection, Key Replacement, Loss of Personal Belongings, RSA, Zero Depreciation, Tyre Protect.

Mods/ Accessories:

  • The big tickets under this heading are Arka/ Avo suspension, 3M full body PPF (except rear door), Under-boy protection, and the TJ-style 7-slat grill.
  • While I have covered all the accessories elsewhere in this thread, I will post some updates esp. on the Avo suspension later.

Maintenance and running costs:

  • If I had followed the recommended schedule, I would have spent about ₹ 0.85 per KM on maintenance.
  • I carry out additional stuff - changing engine oil at the 1,000 KM service, changing the differential oils every service, etc. This has increased my cost per KM on maintenance to ₹ 0.95 per KM.
  • I am planning to switch to 5,000 KM intervals for engine oil changes now on, with the M&M Maximile oil itself, so this cost will increase a bit more.

An interesting trend on the cost of consumables:

If you are an entrepreneur, think about opening up a DEF manufacturing unit - the prices have increased by 70% per liter in 1.5 years!!!

Among the other maintenance consumables, Engine oil prices have gone up by 26% per liter, while that of differential oils are up by 20% per liter. Prices of the filters have remained unchanged though!

DEF, DPF, SCR:

As always, I have had ZERO DPF related issues with my Thar through the 40,000+ KM of ownership. The closest I have come to having an issue was this:

This came up right after the 30,000 KM service, and went off after about 3 driving cycles/ 50 KM of driving.

What was interesting, my Thar had just about gotten a service action for replacement of Engine Wiring Harness, and I was awaiting parts to arrive. As soon as this came up, I raised my panic flag because I was about to do a road-trip for work (~2000 KM), and didn't want to be stuck. Thanks to Mr. Sihabuddeen and Mr. Ronald (M&M), Mr. Dilip & team (CAI Mahindra), getting the part was expedited so that I can travel without this worry in my mind.

The others were only DEF related warning, when I am running low on DEF, with a headroom of 2,400 KM before I am stranded.

I have been using the Thar in city traffic exclusively and continuously for about 2,000 KM in Coimbatore, and 1,000 KM in Hyderabad. Never faced a manual regen situation. Heck, my daily usage for the last 3 weeks were 10 KM to and fro office in peak traffic, which takes me about 30 minutes.

I strongly believe that at least M&M does not have DPF malaise, and anyone who faced one in their Thar invariably changed their Engine Wiring Harness - which leads me to believe it was a wiring issue rather than a DPF/ SCR system related issue.

What would be nice though - having a DEF level indicator in the MID, along with a DPF filter %/ indicator. M&M, please give us a software update with these!

DEF consumption:

I have not decoded why I got a great DEF mileage during the first 10,000 and the last 10,000 KM of usage - nothing stands out when I look at my pattern

Service action:

I had one - the engine wiring harness replacement:

  • Thermal Bypass Valve Replacement (this is for the AT transmission - the valve had a leak) (20-Mar-2021 - Inspected) (28-Sep-2021 - Replaced)
  • Wiper Motor Breather Cap Addition (20-Mar-2021)
  • AT Shifter Screw Retighten (20-Mar-2021)
  • Seat Shoulder Bezel Shaft Replacement (20-Mar-2021)
  • Remove 4WD Shift Cable from Mounting Clip (20-Mar-2021)
  • Camshaft Replacement (20-Mar-2021)
  • Hood Catcher Replacement (20-Mar-2021)
  • Radiator inlet Hose Clamp Addition (28-Sep-2021)
  • Instrument Cluster Software Update (28-Sep-2021)
  • AT Pigtail Replacement (28-Sep-2021)
  • Hood Latch Assembly Replacement (27-Nov-2021)
  • E-Disconnect Connector Cap Addition (25-Sep-2021)
  • Radiator Assembly (29-Jan-2022)
  • Fuse for Radiator's fan (22-02-2022)
  • Engine Wiring Harness (24-06-2022)

The original part that came with my Thar - part # 1801AW500400N Rev F.

This guy flew in for me - thank you M&M and CAI teams!

The revised part # is 1801AW500950N.

All installed, in place - ready to be tested!

Turbocharger actuator link, auto tensioner and belt replace recalls have not started reflecting for me, this has been posted in Sep '22 - makes me think either these are not official or do not apply to my Thar.

Driver footwell getting warm/ hot:

I finally have the official answer to this "feature / mystery" that was pointed out by many BHPians:

This is a part of the exhaust assembly, and is downstream of the DPF/ Catcon - and gets as hot as 400° C apparently.

So my hypothesis that the heating has to do with the AC Temperature knob being set to mid/ warm/ heating is out of the window - there is no lines related to the air conditioning anywhere near the driver footwell! And @Slipstream11 got it right - it is related to the DPF/ Catcon - their downflow, to be precise.

During my recent trip from Hyderabad to Madras, I was driving with the temperature dial midway for a few 100 KMs and there was no heating. And then I noticed it:

The MID flash something about DPF being clogged (the fraction second warning that does not stay). And then it started - the footwell started to get warm and eventually hot. It lasted for about 30 min before things started going back to normal. And during this time, the mileage dropped 2 KMPL even though I was doing constant speeds, mostly on cruise control.

So I guess if your Diesel Thar's footwell is getting warm, it means your DPF/ SCR is working fine - that is one worry less, ain't it?!!

Workaround? Get something like ULS 7D Economy Mats from Autofurnish - you will still feel the warmth, but it never becomes uncomfortable.

That's it today! I will post an update on AVO Suspension soon - as well as a few other itsy bitsy updates!

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