Rear Diff. gear change
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Lead Driver
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From: Norco,CA
Rear Diff. gear change
Ha guys, do any of you in the Riverside, Ontario San Bernadino area, California know of a good reliable shop for Diff. gear changes. My son has a 04 PSD 4x4, that he wants to go to 4.30 or 4.56 gears asap. He tows 16 to 18 thousand pounds he thinks with his custom weekend warrior 40 foot. He picked this thing up right used but didn't think how heavy it was. I've never done rear ends and didn't want to start the first one on his. Thanks your help its
appreciated. God bless, Chet
appreciated. God bless, Chet
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Lead Driver
Joined: Sep 2005
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From: Norco,CA
Tuned
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From: Boulder City, Nevada
A lot of guys on this site are towing more than that and having little problem. But California has the high temps, extreme mountains, and of course the troopers there are much stricter than most. With that said and with that gearing I think you would have little problem towing the trailer.
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From: SoCali!!
Ha guys, do any of you in the Riverside, Ontario San Bernadino area, California know of a good reliable shop for Diff. gear changes. My son has a 04 PSD 4x4, that he wants to go to 4.30 or 4.56 gears asap. He tows 16 to 18 thousand pounds he thinks with his custom weekend warrior 40 foot. He picked this thing up right used but didn't think how heavy it was. I've never done rear ends and didn't want to start the first one on his. Thanks your help its appreciated. God bless, Chet
appreciated. God bless, ChetHow much tire does that truck have? I am assuming it is stock height due to the trailer he is dragging.
If it has a stock height tire, the 4.30's will do, but if it has any lift with even a slightly taller tire, the 4.56's may be his best bet.
I run 4.30's in a 7.3 and a 6.0 truck, both with 38" tall tires, but the heaviest trailer I tow is 14k.
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Joined: Nov 2008
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From: CA Sacramento
Ha guys, do any of you in the Riverside, Ontario San Bernadino area, California know of a good reliable shop for Diff. gear changes. My son has a 04 PSD 4x4, that he wants to go to 4.30 or 4.56 gears asap. He tows 16 to 18 thousand pounds he thinks with his custom weekend warrior 40 foot. He picked this thing up right used but didn't think how heavy it was. I've never done rear ends and didn't want to start the first one on his. Thanks your help its appreciated. God bless, Chet
It does not seem like he has mpg in mind so 4.30 or 4.56 will both do well if he is on stock tires.
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Joined: Dec 2004
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From: norco,ca
Hey guys I am the son Chet has been talking about. I looked up Diff works and they seen to be local and a good place to start. Any Idea of what I should expect to pay for front and rear gear changes?
My truck is lifted 6" and has 325 tire size. The gears are what needs to be installed before I load this trailer up for sure. Ive towed empty to the river a few times now and the trucks does well. but when I load this monster up its gonna be fun.
SoCal, With your tire size is there a reason you didnt you go with the 4.56?
Thanks for the recomendations!
My truck is lifted 6" and has 325 tire size. The gears are what needs to be installed before I load this trailer up for sure. Ive towed empty to the river a few times now and the trucks does well. but when I load this monster up its gonna be fun.
SoCal, With your tire size is there a reason you didnt you go with the 4.56?
Thanks for the recomendations!
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More Turbo
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Getting an air bag kit(FIRESTONE) for the suspension will help level it out and not stiffen it up
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From: SoCali!!
Hey guys I am the son Chet has been talking about. I looked up Diff works and they seen to be local and a good place to start. Any Idea of what I should expect to pay for front and rear gear changes?
My truck is lifted 6" and has 325 tire size. The gears are what needs to be installed before I load this trailer up for sure. Ive towed empty to the river a few times now and the trucks does well. but when I load this monster up its gonna be fun.
SoCal, With your tire size is there a reason you didnt you go with the 4.56?
Thanks for the recomendations!
My truck is lifted 6" and has 325 tire size. The gears are what needs to be installed before I load this trailer up for sure. Ive towed empty to the river a few times now and the trucks does well. but when I load this monster up its gonna be fun.
SoCal, With your tire size is there a reason you didnt you go with the 4.56?
Thanks for the recomendations!
If you drive like a grandma when it is empty it won't matter, but if you drive hard, the 56's may not be the right choice with the tire you are running. The 30's may be the better choice, even towing heavy.
Find an RPM/Speed calculator online and punch in some numbers, it should help you decide.
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From: SoCali!!
A stock tired (265/75/16) early truck with 3.73's and an auto (4r100 or 5r110), which has an OD gear ratio of .71, will turn 1943 RPM @ 70 MPH.
Same truck, 35" tire, 4.30's, 2025 RPM @ 70 MPH.
Same truck, 35" tire, 4.56's, 2145 RPM @ 70 MPH.
I love the 4.30's, I have put them in a bunch of trucks (including two of my own), but if this were my truck, and I was dragging that BAHT, I would gear it for all it was worth, and install the 56's.
Same truck, 35" tire, 4.30's, 2025 RPM @ 70 MPH.
Same truck, 35" tire, 4.56's, 2145 RPM @ 70 MPH.
I love the 4.30's, I have put them in a bunch of trucks (including two of my own), but if this were my truck, and I was dragging that BAHT, I would gear it for all it was worth, and install the 56's.
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Lead Driver
Joined: Sep 2005
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From: Norco,CA
You guys are great. His concern is the trailer, 2 quads, one rhino and one razar all water, fuel etc., this is a weekend warrior custom, 3905 flipped axles and it is tall. Trailer labeled at 16K but previous owner says it ways more loaded. I'm not sure what RPM he would turn at 80mph, unloaded of course, like going thur Utah, but with that weight pulling I believe 4.56 would be best. One diffferencial shop up north said go 4.88, but I think that would put him out of the everyday driving if needed. Chet
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Joined: Sep 2008
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From: Central NJ
I had a 03 F350 6.0 crew SRW LWB with 3.73's and I still have an 06 F450 6.0 crew with 4.10's (which of course is dually) and I tow a 10k trailer on a regular basis. I used the 450 more then the 350 for 2 reasons. The stability of the dual tires and heavier springs and the gear ratio meant the engine/trans was not working so hard. With an 03 6.0, I could see blowing a head gasket, a turbo or head bolts. I liked the dual so much ended up converting the 350 to a dual, but it was a utility truck. Just my .02