All this, plus, they dialed down the temp gauges as well to keep people from complaining. Plus-Plus, I still don't see how they get away with stating in an owner's manual the fluid change intervals. Complete bullshit. I'll never buy or recommend a modern Rover. I tell everyone who asks, which is a lot, to stay away and buy a Land Cruiser.
D1 fuel economy
- Thread starter terryjm1
- Start date
I have them in 2 D1s. Between the two I only have about 2500 miles usage. But, so far they work perfectly. FWIW - 2020 price $109.99, 2022 - $129.99. - currently $149.99.
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I am learning first hand the crappy way the temp gauge works. Between 180 and 215 it barely moves if at all. It may not move at all until even higher temps are reached as that is as high as I got mine on the last run. Mine made it to the top of the “normal” range (before I had a reader/scanner plugged in to monitor) and as such I have no idea how hot it got. I have a new fan clutch on order as that is the cheapest next step. If that changes nothing it’s onto taking out the radiator. This is in a very low mile engine with a new flowkooler water pump. It runs perfectly with no outward signs of an issue other than the AC fans staying on after I turn off the AC. On the fan clutch, I’m optimistic that is the problem as it moves a lot less air than my other D1 which came with a new fan clutch. The radiator is also very low miles. It came with the engine.
This hasn't been my experience. I run an OBD2 app on my phone that reads the temps from the ECU. The ECU is about 5 degrees lower than what an IR gun tells me the thermostat housing temp is. I've been past the middle many time on long steep grades. I don't pull over until I get beyond 215. I installed a toggle switch to run my condenser fan from inside the truck. That helps knock off a few degrees on 100+ degree days. I'm trying to nurse this old girl to 250k+ if possible before HGs and rebuild.
"Past the middle" is well beyond 215 on my gauge and temp sensor. If your OBD2 readings are that far off of what an IR thermometer is reporting I'd be suspicious of your sensor. edit: I thought I read 15 off, not 5. 5 I believe, and is because you're measuring the outside of an aluminum neck, not water temp with your IR gun.
Then again, I've seen different behavior from a lot of these trucks in more ways than temp gauges, they're 25 years old and full of worn out and/or aftermarket parts, bad grounds, crusty connectors so I suppose it's getting harder to say with certainty how any of them will react with specificity.
But one thing reported over and over and over through the years on these vehicles that absolutely matches my direct personal experience with several of them (including D2s!) is what you responded to.
Then again, I've seen different behavior from a lot of these trucks in more ways than temp gauges, they're 25 years old and full of worn out and/or aftermarket parts, bad grounds, crusty connectors so I suppose it's getting harder to say with certainty how any of them will react with specificity.
But one thing reported over and over and over through the years on these vehicles that absolutely matches my direct personal experience with several of them (including D2s!) is what you responded to.
I had to replace the sensor in one of mine and the britpart or whatever it was has a much different curve than the OE. needle moves at about 205 vs 230
Yikes, this is the kind of thing I'm talking about. The sensor gets used for several things that are a lot more important than moving the dumb gauge. It shouldn't have a "curve" it should report exact temperatures.
Who knows at this point: you could be the one in this thread with an actually working and properly reporting gauge. I've not strapped a thermocouple to mine while driving around to compare the relevant temperature ranges to see how accurate they are compared to the OBD PID. Maybe I should.
I have two thermocouples in the upper rad hose about 8-10" downstream of the thermostat housing. They read 1 - 2 degrees F hotter than the Ultraguage OBD2 (steady state thermostat fully open).
Watching the temps has been an education. From cold the factory sensor temp rises much faster (no surprise, only a small amount of coolant is getting through the small hole in the closed thermostat). My thermostat opens at 179.6 F. Temperature on all 3 guages then rises rapidly 3-4 degrees. I believe this is an indication the hottest coolant in the engine is not right behind the thermostat. Seconds later coolant from the radiator enters the engine and all guages drop - the factory sensor leading. Then the thermostat closes (!) at least partially. The hottest coolant is in the upper rad hose at this point. A few more seconds and the temp reported by the factory sensor starts rising while that in the rad hose falls. And this seesaw continues until I'm warmed up and on a straight stretch with no hills etc. This is why I mentioned a steady state in my earlier post. None of this is surprising but I'd never really thought about how active the thermostat might be. Setting the set points for the electric fans forced me to think about what was going on. It would be hard to find a point in time where the OBD2 temp and an IR gun agreed for instance.Maybe we should all send your our sensors to swap in and out to test
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Just got back from a trip up the mountain. It went from 215 to 235 rapidly, in just a couple minutes, before I could pull over. 235 on mine was just a tick over the top white line. On the way down it dropped to 177. I really think I am going to need a radiator. I will try a new fan clutch but I don’t think it will help considering it doesn’t get hot with slower stop and go driving with the AC on in 90 plus weather. The gauge moves a lot between 225 and 235, by the way.
Hope I didn’t damage the engine. It showed no signs whatsoever as far as how it ran whether at 177 or 235.
Hope I didn’t damage the engine. It showed no signs whatsoever as far as how it ran whether at 177 or 235.
I've tracked every fill up with miles driven since late 2018 in my '96 D1 with a 5spd. All done via the odometer except for long road trips where I can use Google maps. Keep in mind this includes plenty of low range driving. All data is with 2" lift and 235/85r16 tires. Most recently with front ARB and winch combo plus sliders. Always premium fuel.
Total miles = 17,810
Average MPG = 12.9
Median MPG = 12.8
Fueling Count = 91
Total miles = 17,810
Average MPG = 12.9
Median MPG = 12.8
Fueling Count = 91
My 95 R380 (5sp stick) with same tire size (perfect size for an emu lift, imo) is exactly the same. With 235/70/16's and all dialed in I was actually hitting 17.5-18mpg in the flatlands (WITH a rack).. which was amazing... but with the 85's the mileage dropped way back down to it's "traditional" range.
*17-18 was with the electric power steering.
The taller tires are the cause of the mileage hit. I when from ~29.5" to 32" ... like adding an overdrive. My current engine is the original 3.9 with 205k miles and the original camshaft... lets just say it feels a little flat. I am gonna be building a 4.0 into a 4.6 and popping it in there at some point. Not sure if I will keep the 14cux or use the GEMS or.. some aftermarket 'puter... open to suggestions