My tentative calculations for my 1994 E420 come out to about 16 city/25 highway.

Hardly hybrid numbers ...but does that sound about right for these engines?

What are you getting?

but my 84 500c
sec will do 19 on the highway at 65 mph and i doubt that the 420 will do all that much better. i guess 15% better.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I drive my 96 S500 Coupe M119 about 130 miles every day (about 65 miles each way to work). Parts of the commute are 70 mph and parts are bumper to bumper at a crawl. Takes me easily 4 hours a day on the road. Gotta love this Washington DC traffic!
My gas mileage is 21 mpg combined... every time.
I've gotten mid to upper 20's on a long trip.

Not bad for a heavy car with over 300 hp.

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KenP

1996 S500 W140 Coupe

I got 25 highway from a recent trip down to orlando from atlanta. no traffic, flat road and I was using cruise control for hours. I got like 340 miles off a tank...and I was refilling somewhere in the 14-15 gallon range....so like 340/14 = 24.2, or maybe 340/15=22.67 at the worst

...so sue me for my significant figures but its in the ballpark. I just figured the city the other day and it was like exactly 16.0...kinda funny.

Your numbers are spot-on for a W124 400E/E420 - my all time high was 26.9MPG on the highway and typical figures were 24-26MPG.

Same numbers with my .034 E420 during the weekly commute. Unless the driving conditions vary a lot (not likely), fuel economy is spot on whenever I refuel. Highway trips turn around 27-28mpg where the distance is at least 100 miles.

Like you said, not bad at all

-DM

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1995 E420 SE black/black
2004 Volvo V70R AWD

I just averaged 26-27MPG on a 600 mile trip in my '95 E420. Better economy than my old '82 240D!

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2002 500SL(Black/Black)
1992 300SE(Black/Black)
1992 190E 2.3(White/Navy)
1999 VW Jetta TDI(Pearl Green)
1986 SAAB 900 Base 3 door(White)
1983 Porsche 911SC(Chiffon)
1977 VW Scirocco(DiamondSilver)

This is for an all-city driving, with lots of cold starts, stop and go, short trips.

17mpg. When I do 50% highway driving (the rest are short trips in the city), I get about 21mpg and best was 25mpg (75% high speed highway driving)

Not bad I think..

Can't beat my 85hp Ford Escort though. 80mph blast to NYC and I average 44mpg! It sure felt SCARY at 80mph though.

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2008 BMW 335i Coupe

Well... on these cars, keeping your foot out of the pedal is the key to decent MPG. My E500 gets 16-18mpg around town, and low 20's on the freeway. On the one long trip it's been on (driving home after purchase), I think it got 23mpg, which included a couple of blasts towards the speed governor (conditions precluded actually hitting it, though, bummer.) Probably would have been 24+ had I kept it under 90, lol. I'd say your numbers are quite good.

Side note for you 400E/E420 owners... if you want to spice up your ride a bit, swap out the anemic 2.26 axle ratio with the 2.65 ratio that the Euro models received (or bump up to 2.82 for a little more ooomph). Minimal loss in MPG or top speed but a BIG gain in responsiveness. It's a straight bolt-in if you get the proper salvage yard donor diff (from a W140 or R129).

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Dave
Boise, ID
Check out my website photos, documents, and movies!

oh man, this car suffers from hella turbo lag! well at least thats what I call it. I havent called around yet, but its something I want to do. Any idea what a used diff goes for?

Due to the bike rack on the roof of my car I usually average about 20mpg. It seems to always hover around that mark, no matter if it's highway or city.

I also live in San Francisco so driving in the city is as bad as it can get, with all the hills a such.

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1992 Mercedes-Benz 400E
2002 Mercedes-Benz ML500

Most used diffs are in the $300-$500 range, depending on availability & demand. If your car has ASR you need an ASR donor diff, and vice-versa. If you're content with the 2.65 diff I believe those are plentiful and cheap from an E320 but requires swapping the rear cover and all flanges. There's one from a W140 that I think has the correct flanges, I'd need to look at that again though. The 2.82 ratio would make it even quicker but you would REALLY need to put fatter wheels & tires on by that point, the silly 195/65's on 6.5 wheels would be crying 'uncle' pretty quick. If your 400E has ASR, a 500E diff should bolt in, but those are awfully rare due to the handful of 500E's imported in the USA.

I had started a listing of differential specs & part numbers, to see what diffs will easily swap. However I only completed the W124 info, I did not get all the R129 and W140 data. I'm working on it though. Here's what I have so far (small PDF file) :

http://www.w124performance.com/docs/mb/other/differentials.pdf

Ack - just realized the limited 129/140 data is only on my Excel spreadsheet, I didn't put it in the PDF file. I'll need to rectify that too. Note that changing the axle flanges is not really a big deal, but changing the driveshaft flange (at the flex disc) IS a really big deal, as it's also the pinion crush sleeve preload... this is best left to a dealership, IMO, unless you have the special tools needed.

Attached Files

differentials.pdf (8.3 KB, 678 views)

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Dave
Boise, ID
Check out my website photos, documents, and movies!

1997 E420, I am getting a combined 21 mpg's, which includes city, light highway, and some freeway driving. I never asked, researched or even considered mpg when I bought this car three weeks ago. I primarily wanted a smooth, reliable, and powerfull 8 cylinder Mercedes-Benz engine. Now that I have all of this- gas prices have gone through the roof- but to be perfectly honest, I could care less.

p.s. I did however begin to purchase gasoline at Costco...I think I save about 20 - 30 cents/gallon.

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My cars

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1997 Mercedes-Benz E420
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1971 Jaguar Series-1 XJ6
1965 Karmann Ghia Coupe
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Let me know where that Costco is! My Costco only saves around 5 cents a gallon at the most!

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1992 Mercedes-Benz 400E
2002 Mercedes-Benz ML500

Here's a writeup on the differential swap, with photos:

http://tom.actionfit.com/2_82_Differental_Swap.html