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Trip report - test drive 3.70 LSD [message #248352]

Thu, 24 April 2014 08:18

SeanKidd

Messages: 747
Registered: June 2012
Location: Northern Neck Virginia

Karma: 4

Senior Member

Unfortunately this report will not include my new P.Huber torsion bars, they arrived as we were packing the coach for spring break.

First trip of the year and our longest yet, not all the numbers in yet. First impression of the 3.70....awesome! Nearly 800 miles round trip from north west NJ to Virginia Beach via Chesapeake Bay Bridge Tunnel, rather flat, but living in the Skylands region of NJ(no chuckling from the west coast) the warmup trip the day before(about 80 miles) over hill and dale proved joyous. The collective is right! The 3.70 really wakes up the 455...I also have a Melling MTO-1 high torque cam.

This is also the first trip with vacuum gauge and tach. In the flats, 65 mph, 16 in Hg, ~2800 rpm. Return trip had serious headwind and in some cases had to maintain ~12-13 in Hg to maintain 60mph.

I still have some concern about high oil consumption, about a qt per fill up, seems to be diminishing though, just under 2k miles on home rebuild however in my paranoia, broke my dipstick tube on the trip down, it broke at the second "bubble", so there is about an inch exposed. After getting online to identify its exact location (Thorley headers) an trying to find something to stuff in the hole, Stephanie suggested an ear plug. A minor burn later, we were in business, 200 miles later, ear plug did not melt and sealed the tube well, I installed a new one for the 400 mile trip home (after checking the oil level). Drove in the green (vacuum) as much as possible, will calculate mileage after fill up.
2 qt Dino gear oil as recommended, the deceleration whine is not as pronounced after nearly 900 miles. I need to adjust modulator a little more, still shifts into third at 15-20 mph.

Lastly, I noticed occasional surging of the transmission at red lights...rpm and vac needles dipped during surge. I'm on my second trans fluid change in 2k miles, and installed external filter. ( Fluid from PO was nasty, as was the molasses from the FD during its initial fluid change.) new B&M filter is a puralator with integral magnet.

Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers

[Updated on: Thu, 24 April 2014 08:19]

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