Well as most already know I bit the bullet and took my truck in for new set of 4.56 gears and a little freshining of the transmission. I've read and reread all of the things I can find about doing the proper break-in and have obviously read everything from dropping the hammer on the way out of the lot to 1,000 miles of easy driving before any abuse, the most common is 300-500 miles before beating on them with short 20 miles trips plenty of cool down time and keeping the speed below 60 to properly heat treat and break in the new gear sets.

I asked the mechanic installing the gears and he wasn't much worried about it. I stressed to him multiple times that I will be heading to the lake on the 30th with the boat and camper and was worried about getting the break in done in time since I probably won't have the truck back untill Tuesday the 26th. Again he wasn't the slightlest bit concerned, I however am since this is a faily expensive mod that I don't want to do again.

As of right now my plan to do the break in is as follows: pick up the truck on tuesday. I can probably get 2 heat cycles in after I pick it up. I'll use it as my daily driver and drive to and from work wed through friday. It happens that it's 15 miles of mostly highway to the office (perfect for a heat cycle). I'll probably get 3-4 heat cycles in per day from wed thru friday. This puts me around 200-250 miles before saturday. This is where I don't have a lot of choice. Saturday morning I leave for the lake with all the goods in tow for a 8 day camping trip. The trip to the lake is approx. 80 miles. I would be able to stop at about 20 miles for a cool down (first town) and then at about 26 miles for a second cool down (second town). The last strech will be about a 30 mile run on a two lane road so I won't have much choice but to finish off the trip.

I know most say to wait untill 500 miles before towing but I don't have a lot of options. I can probably even get up to 300 miles before the weekend without to much issue but time is kind of against me to get 500 miles in.

How did everyone else that's had gears changed do your break in and how long did you wait before towing? I'll take suggestions but at this point I can only try and log as many miles as possible in the three days that I'll have before leaving and I can't say for sure how many miles that'll add up to.

I know I'll log another 200 miles or better of unloaded driving while I'm on vacation before I come home so I should be go to go by the time I leave.

Lets hear your thoughts.

 

Sounds like your daily drive is perfcet for a break in.
I wouldn't be concerned about towing at all. The gears will be fine.
All I would do is change the oil again. But that's one of my rituals.......

 

I think the 250 miles would be fine to break in the gears. My mechanic said a lot of short trips 5-10 miles at a time breaks the geas in great. My thought is the 500 miles is a large saftey net so to speak.

Just tow like an "Old Man" and it shoud be fine.

Have a fun trip.

 

Are you having a finned aluminum (factory Ford) diff cover installed at the same time?

 

I was planning on chaning the oil after we returned as I should have maybe 700 miles on the new gear set after the vacation. Although I thought about it, being my bill was already gonna be $3,500 or so, I skipped the finned aluminum cover. You never know, I may still add that when I change the oil after breakin. I think it'll be alright but I know it's gonna be hard to tow like an old lady now that this thing is setup to be a stump puller, gonna be hard not to lay into it!

Hopefully I'll get it back today or tomarrow and I'll simply be going for some joy rides untill saturday to log some extra miles. I pawned the wife and the kids off on my inlaws for the ride down as I know they aren't gonna want an 80 mile trip to last 3 hours! The in-laws have a motorhome anyhow so that actually worked out pretty good.

I'll report back with my initial driving impressions and of course after I hook up to the fifthwheel!

 

Well, the gears are in, the trany has had new life breathed into it, the shift stock is back to new, and the keys are in my hand. Just returned from picking up the truck and took it for my initial drive. The shop put on 14 miles or so and I've just finished putting another 19 on it. Took the digital temp gauge with me and after a 20 mile run of mostly 40-50 mph the hottest place on the dif was the front yoke and it was only 125 degrees F. Didn't think the RPMs seem bad but on the other hand I never broke 55 mph and that was only for a few seconds. Rolled into it a little about half way through the drive and although it seems peppier it's awfull hard to tell when trying to drive with an egg under my right foot and no 5-star tune installed (I put it back to stock before I took it in). Truck feels stiff but seems lighter when accelerating otherwise everything appeard good. I did spin the tires a bit leaving the shop in the rain and I was being very easy on it so it'll be interesting when these things are broke in and I can really get after it. I'm sure I've pissed off a few motorists driveing 50 mph in a 65 zone, cann't wait to get a 100 miles or so on them so I can quite holding up traffic! Will update as the week goes on.

 

Keep us posted about how it towes. I am thinking 4.88 for my tuck but have not taken the plung yet.

 

92 miles and counting (4 heat cycles). Should be able to start driving normal speeds after one more trip of below 50 mph or less! I seem to have a slight whine above 45 or so upon light acceleration however I haven't drove over 50 much so I'll report back. Still been babying it so not much to report. I'll have the installer check pinion depth, backlash, and wear pattern when I take it in to get the breakin oil changed (which he threw in the deal after I asked him his reccomendation). I've also been using an IR temp gun after each drive and haven't seen anything hotter than 145 degrees.

 

SLE, i admire your patience as I would have already been stomping on the gas. I must say I find a bit of irony in the quote you at the bottom of your signature compared to how cautious you are being with the new gears.

I have thought a lot about doing gear change myself but am now leaning toward selling and buying an 08-09 f450 since my paid for truck and a little more then the cost gears and I would have one.

 

What I would like to see is a photo of your BSEG the first time you pull with it .

Denny

 

Kind of forgot I had that as my signature. That's certainly irony. It's been really hard not to get on it. I've rolled into it a couple of times lightly and I gave er a little on the gravel spinning both tires for a few feet from a stop but It's been a test of patience trying to drive it nice. I take exceptional care of my stuff but I'm also a guy that likes to use it for what it's made to do be it my ATV, the snowmobiles, the boat, or my vehicles, they all get ran pretty hard and I realy haven't ever broke anything. I chauk it up to proper maintence and fixing stuff before it breaks. It's just like the trans in the truck, it would have probably been fine with a fluid change, filter and a seal however I figured if I'm dropping it to do the seal, I might as well get the pump rebuilt and have a new converter installed. It's just the way I roll.

rvpuller, I'll certainly report back as soon as I get a good test with the train in tow! How about that drag race, lol.

 

I hope you get a test pull soon because we will be leaving for our late summer/fall trip on our way to Florida for the winter, about 6K miles and we will be without internet for a lot of it.
As far a drag race remember with my 215/85/16 stock tires my final gear ratio with 4.3 gears is still lower than yours and with DRWs I get lots of traction .

Denny

 

I'd be up for the challenge; win, loose, or draw! Wouldn't that be a sight to be seen though. I may be able to report on saturday or sunday depending on my phone service otherwise I won't have anything untill I return on Monday Aug 8th. Certainly looking forward to it.

 

I remember when we bought the truck and I picked up a friend and he told me to get on it well I was already rolling and I jumped on it and his eyes got pretty big but then he said I didn't here it squeal, I told him to look behind us because there was 4 black strips about 20 ft long . My Dana 80 in this truck has always locked up fast unlike the LS in my SRW work truck (it now has a new owner).

Denny

 

Well, I'm now up over the 200 mile mark. From a driveability standpoint, I actually think the truck drives better. I can accelerate at will with no problem at all in OD going up any of the largest hills in the area. I'v rolled into it a couple of times now as I've began to drive it somewhat normal without beating on it. From a roll in 3rd gear at 50 mph it seems to pull pretty hard at about 3/4 throttle. I have managed to resist the urge to go WOT so far but it's tougher by the day, lol.

I do notice a slight howl that is most prevlant between 50 mph and 60 mph. below 45 and above 65 you cann't hear it at all. The howl/whine is only when you'r in this speed range and only when I'm on the throttle very lightly. If I'm acclerating, coasting, or slowing down it doesn't do it. I don't know much about gears sets but I would assume this would be a backlash setting that can possibly be adjusted? I'll certainly be having the shop double check things when they change the oil. I also have come to find that my damn OD light on my shifter is still acting up. I believe they simply installed a new shift handle/mechinism which worked perfectly for a day but I'm back at the point where I can move the handle a little and get the light to come on or off at will. There must be a loose connection or chaffed wire or something in there. This is also on the list for the return trip.

I did reinstall the ol 5-star tuner with my 91 octane towing tune and although I'm not sure I think this puppy might actually chirp the tires going into second If I go WOT. So far I haven't been over about 3/4 throttle and that was only a select time or two. Gotta give a shout out to Mike as he emailed me updated tunes very quickly and as always they sure wake up the V10!

So far I'm pretty happy however it still has to pass the real test of towing our 32ft fifth wheel and 20 ft boat (GCWR of Approx 22k lbs). If it passes the towing test I will likely be able to say it was money well spent.