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1994 Cadillac Fleetwood Repair Question


Topics covered: Tire, Towing, Radiator.
Mileage: 115,000 miles.

Asked on August 29, 2011

Upgrade differential ratio

Hi, I am planning on using my 94 Cadillac Fleetwood to tow a camper trailer. The diff. ratio it has is at 2.56:1 (not the best towing ratio).
I plan on upgrading to a 2.93:1 (from a Brougham) to increase the towing capacity to 5000lbs. Will this affect the pcm? Is there a tuning that must be done to the chip?
Avatar Asked by 94fleetwood

Answer

Replied on August 29, 2011

No change there is required, but with the different diff ratio you will get an inaccurate speedo reading, you may be able to change the speedo drive to one for a model with that ratio.

Tiny Answered by mhpautos (expert)
26,882 answers provided
Replied on August 29, 2011

Thanks for your input. The car has 235/75/15 tires on. Originally, it should run on 235/70/15. Would this slight difference in tire size compensate the speedo difference a little?

Tiny Response from 94fleetwood
1 question asked
Replied on August 29, 2011

their is about 4 to five gears with different teeth nunbers.make sure you have a good tranny cooler and a heavy duty radiator if possable.thanks for using 2carpros

Tiny Answered by cadieman (expert)
2,849 answers provided

Replied on August 29, 2011

It is only the dia of the trye that will alter spedo readings, both are 15" so ther is no differance there.

Tiny Answered by mhpautos (expert)
26,882 answers provided