Uphill Acceleration

[MrMarquis]

I know these things are heavy cars...But is it normal for a Grand Marq to kind of top out at about 30-35mph going up steeper grades? I can't get it to move faster than that unless I smash my foot to the floor. It won't shift and continue acceleration. Hell, it doesn't even seem like the engine RPMs change at all no matter how much gas I put to it.

I really hope this isn't normal? But the tranny is new as of last October.

[Grand Marquis GT]

That's 150hp for ya

Lower rear end gears help a lot with this...

[Archangel]

What he said - 3.08 rear gears might be great for freeway driving, but if you're gonna tow stuff or live in an area with plenty of hills you may wanna swap them for something numerically higher. My car doesn't seem to have a problem climbing up steep grades (even from a standstill), but I still avoid straining her like that - instead I just pick up speed on the way downhill, and use the inertia to get me over the next uphill. Better on gas this way too.

[nitroracer]

My car is the same way, it refuses to downshift unless you floor it. So I downshift for it. Just remember to put it back in drive once you get up the hill.

[85MercPark]

That's 150hp for ya

Lower rear end gears help a lot with this...

155 actually

[85MercPark]

My car is the same way, it refuses to downshift unless you floor it. So I downshift for it. Just remember to put it back in drive once you get up the hill.

You can adjust that you know?

[mrltd]

Your car must have issues, my 2.73 and 3.08 geared cars never had any issues with hills. I also make sure to downshift. TV cable/rod must need adjustment.

[88Vic]

155 actually

No, 150HP if you have the single exhaust, and 160HP for dual. I don't know what the torque difference for single and dual is, which is what maters for acceleration. Horsepower helps more at high speeds.

[nitroracer]

It is adjusted. I dont shift into OD until about 60mph. It just doesnt like to downshift.

[85MercPark]

No, 150HP if you have the single exhaust, and 160HP for dual. I don't know what the torque difference for single and dual is, which is what maters for acceleration. Horsepower helps more at high speeds.

Nope, 155, the 85 wagons had 155 with single exhaust.

[gabegt90]

What he said - 3.08 rear gears might be great for freeway driving, but if you're gonna tow stuff or live in an area with plenty of hills you may wanna swap them for something numerically higher. My car doesn't seem to have a problem climbing up steep grades (even from a standstill), but I still avoid straining her like that - instead I just pick up speed on the way downhill, and use the inertia to get me over the next uphill. Better on gas this way too.

yeah same with me going fast down hill Also helps with higher gears I thankful I have 3.55 gears

[88Vic]

Nope, 155, the 85 wagons had 155 with single exhaust.

Well, he has an 88 Grand Marquis, not an 85 wagon. And I think his car has the single exhaust, which after a couple days will drive you crazy listening to that god-awful sound.

[Mercmarquis]

A shift kit will also help it downshift. At the tiniest strain my tranny will downshift. It can get annoying but I can power through most anything.

[87mefull]

Your car must have issues, my 2.73 and 3.08 geared cars never had any issues with hills. I also make sure to downshift. TV cable/rod must need adjustment.

I'm with him, I had a s10 blazer with a 2:73 posi and a 2.8liter TBI v6 that managed to maintain a top speed of 43mph on the steepest of hills.

Is your foot to the floor when your climbing these hills? Is the engine screaming (4000 rpms) or does it sound quiet or low, such as when your first shift into overdrive? If its quiet and low, its not downshifting properly.

First, check the TV cable and the tv cable grommet, these are the two most common problems with our cars. Please replace the tv cable grommet if its old, worn or broken, otherwise it will kill your tranny. The check the settings for the TV cable, there is a thread here about adjusting it. If your not sure how to do it, a good tranny shop should be able to do it without any problems, its pretty easy.

Check for vacuum leaks and scan for codes, a failed sensor or a vacuum leak will cause a big power loss in these cars. If you haven't done a basic tune-up, your car won't have enough power also. I have 3:27's in my car, which are decent performance/towing gears and my car struggled up hills until I tuned the car up. A TPS sensor thats not set properly will cause this type of problem too, it should be set at .98 to .99 volts.

If its not any of the problems listed above and the car runs fine (not throwing any codes), you probably need better gears. These cars use a very common and popular 8.8 inch rear, so you don't need to swap out an entire rear-end for better gearing. Get a track-lock differential if you don't have one and a rebuild kit, unless you take it to a shop to do it. I like the 3:27's in my car, it moves great with them and still gets great gas mileage. My car came stock with them (Axle code 5 ), and I don't have a problem getting up hills with them.

3:55's are a great upgrade for better performance and are great for tow-package cars. Might loose 1-2mpg on the highway but your in town mileage will increase alot, not to mention you won't need to floor it up hills.

[gabegt90]

hey scott bowman do you drive on 70 coming from hagerstown toward frederick that 1st hill a bitch