Im thinkin about ordering my gears on friday and i was lookin at pro 5.0 3.90. Does anyone know about the quality of these gears? Are they worth getting or should i just go with Fords gears? I know FMS or FRPP are the best fitting but they dont make 3.90, they only make 3.73 or 4.10.
personally i would go with the ford motorsport 4:10s, its not a huge jump from 3:90s and you will feel only a small difference if you were to go from 3:90 to 4:10. if you have stock gears you will feel a huge difference from stock to 4:10 or even from stock to 3:90. but ide get ford because of better quality.
I have the pro 5.0 3.90 gears. My installer said they were a bitch to settup and i get a slight gear whine. When i got them put in i had pulled the rear seat so you could hear everything, i havent put a delete in yet. I think the installer is at fault here though. Dont let that scare you away cause i know of other people on here with no gear whine with pro-5.0 gears.
he charged me 250 to set up the gears, put in an auburn pro and swap the axles to 31 spline.. So theres a little more work then just changing the gears since the axle bearings need to be changed, studs need to pressed in and so on.
Gear whine or howl is from the improper pattern setup. Once everything is removed from the rear differential housing, or the 'pumpkin', the pinion is set up first. The tricky part is that you have one time to set it up correctly, or your screwed. The crush collar that is included with the gears is only made to be 'crushed' once, and that is when you are setting up the pinion. Torque on the pinion is measured in inch-pounds, not foot-pounds, and most mechanics and shops do not use an inch-pound wrench to set up the pinion which leads to whine or howl because the pattern and depth are wrong because the pinion was never set up properly.
Now, I'm not saying that those guys don't know what they're doing. What I'm saying is I don't really buy into the whole Pro 5.0 sucks. If Pro 5.0 sucks, MM&FF wouldn't be putting Pro 5.0 stuff into their project cars. I know people on this board will have differing opinions, but I've been around too long to believe that all Pro 5.0 sucks. FMS has a better reputation, however I don't believe that their products are any better. If I were you, I would go into the West Coast forum and ask around for a reputable shop that does gear installs and see if those people have a gear whine problem.
I thought FMS made a 3.90? If you can't get an FMS gear, get a Pro 5.0. If you find a good shop, you shouldn't have any problems.
I have had zoom gears and FMS and actually the zoom was quiet and worked well. The rfeason I went to motorsport was I went to a 4.30 gear the zoom was a 3.73 and I got the zooms from Unlimited Performance for a good price.