Winter Vs Summer Fuel Mileage

[turbo2256b]

Short trips when cold has more to do with how thick the differential fluid you use and if its synthetic or not

[DerekTheGreat]

Tell that to my TBI GM 350 which wants to sit and idle at 1000 RPM until it hits a certain temperature, running rich all the while.

[gadget73]

The diff oil being thick doesn't help though. Synthetic is an improvement there. Also not significantly more expensive, so win.

[Brown_Muscle]

Interesting, i suppose it's good that I'm getting on par fuel mileage. I use 10W-30 synthetic oil. Being cold does not help at, all as mentioned...I don't think the car's even fully warmed up until 1/2-3/4 of the way on my normal trip when it's cold. If I went 65 and got 20mpg...it really wouldn't be worth the 2 extra miles I got to slow down, not to mention people trying to run me off the road at that speed!

I do wonder how its highway mileage would be with 3.08's or 3.27's. Probably not worth the trade off for many reasons, besides acceleration, I do more in city than highway. What was the
"standard" gear ratio for wagons without the tow package? I hope not 2.73s...

[gadget73]

Synthetic specifically in the diff is what I meant. It flows better when cold.

[turbo2256b]

Interesting, i suppose it's good that I'm getting on par fuel mileage. I use 10W-30 synthetic oil. Being cold does not help at, all as mentioned...I don't think the car's even fully warmed up until 1/2-3/4 of the way on my normal trip when it's cold. If I went 65 and got 20mpg...it really wouldn't be worth the 2 extra miles I got to slow down, not to mention people trying to run me off the road at that speed!

I do wonder how its highway mileage would be with 3.08's or 3.27's. Probably not worth the trade off for many reasons, besides acceleration, I do more in city than highway. What was the
"standard" gear ratio for wagons without the tow package? I hope not 2.73s...

mOST 3.08 A GUESS BUT MOST I HAVE had a chance to look at are.

[turbo2256b]

here is how i figured how much economy in the wither was affected by rear gear lube.
Going to work would start the car. it had the climate control heating/AC. would let it warm up until the heater fan set auto would kick on. high idle choke mode dropped to normal after a very short period. Coolant temp at this point around 140* took much longer than choke mode.
it was 3 to 4 miles through city streets to the highway and would run it to work another 8 to 10 miles.
Coming home was just the opposite went through the same procedure to warm up the car but the entrance to the high ramp was was a block or less from were i worked.
used a lot less fuel going to work compared to going home. Changed the OEM fluid in my 87 to synthetic economy came closer to the same both ways.
Want to see the difference put some 80 90 wt syn and some non syn lube out in a cold winter day and try to pour it out

[Tiggie]

Open 3.08 seems pretty standard for most wagons from my findings, including my 90. The 88 is 3.27 open. I don’t notice a difference between the two.

[86VickyLX]

What was the
"standard" gear ratio for wagons without the tow package? I hope not 2.73s...

3.08. which is basically a 2.73 in terms of acceleration and such.

[Birdofprey]

My 86 Wagon has 3.08 and the 84 wagon has 3.55

For reference and because I had to search it, Door Axel codes:

8 : Open 2.73
M : Trac-Lok 2.73
Y : Open 3.08
Z : Trac-Lok 3.08
5 : Open 3.27
E : Trac-Lok 3.27
2 : Open 3.55
K : Trac-Lok 3.55


*Edit And the info for looking at the tag on the axle:


-Charles

[turbo2256b]

I believe all boxes most common were 3.08s, PI maybe 3.27, trailer towing 3.55

[sly]

The sticky for the axle codes is in the aero/whale section http://www.grandmarq.net/vb/showthre...258-Axle-Codes

[Kodachrome Wolf]

I believe all boxes most common were 3.08s, PI maybe 3.27, trailer towing 3.55

The 351 equipped Police model I was under a while ago had a 2.73 rear. Not sure about 302 Police models. The ‘87 has a 3.27 open, but I think 3.08 was more common in standard wagons.

My ‘97, like most non-HPP/Police models just has a 2.73 open.

[DerekTheGreat]

I know for certain on at least '86-'89 Town Cars that the base models were standard with a 3.08. Signature Series gave you a 3.27, both open.

[sly]

all of my panthers have come with 2.73 open so far... 88 MGM GS, 93 CV LX, 2000 CV base. The 88 and 93 were upgraded to 3.55L though.