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2009 VW Jetta TDI

http://www.cleanmpg.com/photos/data/508/2009_VW_Jetta_TDI_Driver_Front_Corner.jpg

Current MSRP (MT/AT): $22,270/$23,370
Current Alternative Fuels Tax Credit: $1,300
Current Delivery and Handling: $690

Engineering:

Engine Type: In-Line 4-Cylinder Turbocharged – Direct Injected Common Rail TDI
Engine Block/Cylinder Head: Cast Iron/Aluminum-Alloy
Displacement (cc): 1,968
Horsepower @ rpm: 140 HP@4,000 RPM
Torque (lb.-ft. @ rpm): 236 Lb-Ft.@1,750 -2,500 RPM
Redline (rpm): 4,500 RPM
Bore and Stroke (in): 3.19” x 3.74”
Compression Ratio: 16.5:1
Valvetrain: SOHC and 4-valves per cylinder
Electrically controlled Piezo-Electric injection
Front-Wheel Drive
CARB Emissions Rating: LEV (CARB Certification Doc (http://www.cleanmpg.com/forums/downloads.php?do=file&id=46))
Federal Emissions: Tier II/Bin5
Direct Ignition System

Transmissions:

Gear Ratios

6-Speed Manual Transmission

1st: 3.77
2nd: 2.09
3rd: 1.32
4th: 0.98
5th: 0.98
6th:0.81
Final Drive: I- 3.45/II- 2.76
Reverse: 4.55

RPM at 60 mph: 1,803 RPM

6-Speed DSG Automatic Transmission (available)

1st: 4.04
2nd: 2.37
3rd: 1.56
4th: 0.90
5th: 0.91
6th: 0.76
Final Drive: I- 4.12/II- 3.04
Reverse: 3.99

RPM at 60 mph: 1,864 RPM

Body/Suspension/Chassis:

Unit-Body Construction
MacPherson Strut Front Suspension
Multi-link Rear Suspension
Stabilizer Bar (mm., front/rear): TBD mm/mm
Electrical-mechanical Power-Assisted Rack-and-Pinion Steering
Steering Wheel Turns, Lock-to-Lock: 3.0
Steering Ratio: 16.4:1
Turning Diameter, Curb-to-Curb (ft.): 35.8
Power-Assisted Ventilated Front Disc/Solid Rear Disc Brakes (in.): 11.3/10.2
Wheels: All-Season Tires: 205/55 R16

http://www.cleanmpg.com/photos/data/508/2009_VW_Jetta_TDI_Interior.jpg

Interior Measurements:

Headroom (in., front/rear): 38.5/37.2
Legroom (in., front/rear): 41.2/35.4
Shoulder Room (in., front/rear): 54.8/53.1
Hiproom (in., front/rear): TBD
Cargo Volume (cu. ft.): 16.0
Passenger Volume (cu. ft.): 91.0
Seating Capacity: 5

Exterior Measurements:

Wheelbase (in.): 101.5
Length (in.): 179.3
Height (in.): 57.4
Width (in.): 70.1
Track (in., front/rear): 60.6/59.8
Curb Weight (lbs. MT/AT): 3,230/3,285
Weight Distribution (%, front/rear, MT): TBA
Weight Distribution (%, front/rear, AT): TBA
Cd: 0.31

EPA Mileage Estimates/Capacities:

6-Speed Manual (City/Highway mpgUS): 30/41
6-Speed Automatic (City/Highway mpgUS): 29/40
Crankcase (qt. MT/AT): 5.8/5.5
Coolant System (gal. MT/AT): 8.7/8.2
Fuel (gal.): 14.5
Required Fuel: Diesel

http://www.cleanmpg.com/photos/data/508/2009_VW_Jetta_TDI_Driver_Rear_Corner.jpg

Interesting that they offer both an MT and a DSG. I thought the idea with the DSG was that it would be standard and replace both the MT and AT. Perhaps they still want to have the lower price of the MT as a draw and then get people to option up $1100 to the DSG as they are already accustomed to doing with the AT.

Obviously we'll have to wait until the final drive ratios are published, but if they are the same for the MT and the DSG, the DSG will be geared shorter than the MT in first (to improve accel?? or perhaps reduce clutch wear when starting from a stop??) and longer in sixth (for better mpg??). Yet there is still a 1 mpg difference in FE in favor of the MT??? I thought the DSG's were supposed to be as efficient as an MT, so where is this difference coming from?

Hi John:

___I have "official" ratios including finals but they do not make any sense :confused: I will have yet another call into VW asking for clarification.

___As an example, the MT's 4th is taller than the 5th and in the DSG based AT, 4th is only .01 shorter than 5th. The finals of both the MT and AT have two ratios shown for a total of four. Again, I have no idea which is real and which is a mis-print.

___For a vehicle that has been out as long as the 09 TDI has been, I am really surprised the Press Kit and posted information around the web is still screwed up?

___Good Luck

___Wayne

A popular mod for the 5 speed (2006) manual transmiddon is a 5th grar swap out. They replace the standard 5th gear with a .681 or even a .653 5th gear. I don't know what is available for the 09.

Comparison below:for the stock .756 and the new .681 5th gear\ in an 06 5 spd.

1900rpm (torque peak): 53mph before, 57.3 after
2000rpm: 55.8mph before, 60.3 after
3000rpm: 83.7 before, 90.4 after!

65mph: 2329 rpm before, 2156 after
75mph: 2688 rpm before, 2488 after
85mph: 3046 rpm before, 2820 after

That looks like a very worthwhile gear swap to me!

It cost about $300-$400 for the gears themselves and anther $300-400 to have them installed.

Hm. That's a bit on the pricey side but I guess not much when some of these people spend more than that on rims. :eek:

Hm. That's a bit on the pricey side but I guess not much when some of these people spend more than that on rims. :eek:

Not too bad it you can install them yourself. I have considered doing it, but have not convinced myself of the benefit yet. Right now, The highest torque range is at 1750-1900 RPM which is right at 50-55 MPH in 5th gear. If I do the swap, then 50-55 will be at 1100-1300 RPM, almost in the lugging range. So I would have to speed up to about 60-65, and I am not sure if the added aero drag will not more than offset the lower RPM fuel savings.

Ah. Good point.

Not too bad it you can install them yourself. I have considered doing it, but have not convinced myself of the benefit yet. Right now, The highest torque range is at 1750-1900 RPM which is right at 50-55 MPH in 5th gear. If I do the swap, then 50-55 will be at 1100-1300 RPM, almost in the lugging range. So I would have to speed up to about 60-65, and I am not sure if the added aero drag will not more than offset the lower RPM fuel savings.
I also thought of doing the swap but had the same concerns. It would be better at highway speeds, but I'd lose the ability to use 5th in a lot of situations in the city. For somebody who does a lot of highway driving, it would probably be worth it. And the price isn't quite as bad as it looks. A shadetree mechanic who can follow directions can do the install themselves and there are a few gasser drivers on vwvortex who would be interested in buying a TDI 5th gear to lower their rpm's. So that gets a bit of the money back in the end, bringing the total cost down to about $300 if the install was a DIY job.

Wayne, I think there are actually two final drive ratios for each transmission. One is used for gears 1-4 and another is used for 5-6.

The longest available is .658

It's a 1 hour job so really it should cost less than $100 to get it installed. You can even sell your old stock TDI 5th to gassers.

The longest available is .658

It's a 1 hour job so really it should cost less than $100 to get it installed. You can even sell your old stock TDI 5th to gassers.

It may be a 1 hour job for you, but with my thumbs it is many hours.

It may be a 1 hour job for you, but with my thumbs it is many hours.

Oh not for me, but for any mechanic you would pay it is. You just pop up the trans cover, pull the 5th gear set and slide the new one in place. That's why I felt 300-400 to get it installed is way too high.

Is the TDI 5th actually smaller than the gasser 5th? I had assumed that they were the same but that the gasser had a shorter final drive, since the gasser gears are shorter across the board.

If you guys are right, then I could just buy a .658 for my TDI, and then swap the TDI's 5th into my gasser. Two problems solved with only one new part!

The final drive is different and some of the gears are as well. I believe the TDI is the only engine that uses that .756 5th. I've heard of the 5th gear swap being done from TDI to 1.8T, but not TDI to 2.0. You should probably make sure that the 5th is interchangeable between the two. I suspect that they are.

On the specs, the coolant capacity should be in qts, not gallons.
Turbocharged engines, both gas and diesel, have a lower compression ratio than their natural air counterparts. This hurts their fuel efficiency. Thus, I'm dissapointed that this new TDI at 16.5 to 1, is so low. I would like to see a ratio of about 23.5 to 1. But of course, the turbo adds power and performance (which I don't care about)

I wish the engine was about 1.4 liters, and the vehicle weight was about 2300 lbs rather than 3200. Much too big of car for me.....

I agree with you on engine size and weight, Bill. A 1.4L TDI weighing around 2500 lbs would be about perfect for me.

Speaking from a diesel point of view, higher compression ratios improves theoretical efficiency, but the gains aren't huge. There are actually a number of reasons to aim for lower compression ratios. Higher compression ratios generally lead to higher NOx, particulate emissions, noise, roughness, and cost. Honda's i-CTDi runs at 16.7:1 and they found that lower compression actually helps efficiency at low loads, because less work is required to compress the intake air with a lower compression ratio. Many of the newer diesels coming out are in the 16:1-17:1 range. I don't think we will see nearly as many engines in the 18:1-20:1 range like there were before.

The downside to lower compression ratios is that the motor doesn't have to be as strong... meaning diesels might not be as bulletproof as they were.