Anything new on flat towing a V8 4Runner?

[steven1955]

I am looking a various ways to pull our 07 V8 behind our motorhome, and flat towing would be the most convenient. However, Remco is out of the flat towing kit business. (Remco offered a pump that lubricated the transmission of the V8 4Runners while being flat towed, but they have discontinued all such kits and seeming have ended support even for existing kits.)

So, here are the options I have come up with so far, although only Option 1 is a flat towing option.

Option 1: Rear drive shaft disconnect along with manual front locking hubs.

I read this thread: AISIN Manual locking hubs Does this work on a 4rth gen V8?

Option 2: Rear drive shaft disconnect along with a tow dolly that lifts the front wheels off the ground so that they don't spin.

Option 3: Buy a car hauler/trailer. (Here we have to figure out where to put our trailer while on the road and avoid it being stolen. But it offers the flexibility of bringing any car we want, not just the 4Runner.)

Option 4: Sell the 4Runner and buy a Jeep.

Are there any other flat towing options that would work that my Google searches have failed to find?

 

[rwh963]

maybe you should tow the motorhome behind the 4runner!

 

[HutchOven]

I am looking a various ways to pull our 07 V8 behind our motorhome, and flat towing would be the most convenient. However, Remco is out of the flat towing kit business. (Remco offered a pump that lubricated the transmission of the V8 4Runners while being flat towed, but they have discontinued all such kits and seeming have ended support even for existing kits.)

So, here are the options I have come up with so far, although only Option 1 is a flat towing option.

Option 1: Rear drive shaft disconnect along with manual front locking hubs.

I read this thread: AISIN Manual locking hubs Does this work on a 4rth gen V8?

Option 2: Rear drive shaft disconnect along with a tow dolly that lifts the front wheels off the ground so that they don't spin.

Option 3: Buy a car hauler/trailer. (Here we have to figure out where to put our trailer while on the road and avoid it being stolen. But it offers the flexibility of bringing any car we want, not just the 4Runner.)

Option 4: Sell the 4Runner and buy a Jeep.

Are there any other flat towing options that would work that my Google searches have failed to find?

What kind of rv you got? Towing on a car hauler will likely put you over the 5klb (or less) weight limit that 95% of the rv's out there have.

A side note for option 4 is that if you have a bunch of mods to your 4r you could buy a gx and swap them all over and flat tow that since it has the manual case, ditto to a fj but you lose the v8.

Also, for option 1, why can't you just disconnect both Driveshafts instead of hubs? I bet after doing it a couple times you could have both back in in 10 minutes.

 

[KrazedJD]

As much as I laughed at the 4runner towing the RV (also viable option too lol)

For the money of a trailer have you considered the fj-transfer-case-swap? This would allow you to disengage the 4wd all together, and not sure as I do not have the swap but possibly put the transfer case in a neutral position.

 

[steven1955]

What kind of rv you got? Towing on a car hauler will likely put you over the 5klb (or less) weight limit that 95% of the rv's out there have.

Our motorhome is a 1975 FMC 2900R with the original 440 Chrysler Industrial V8 and 727 3 speed auto replaced by a Cummins 5.9 24V diesel and an Allison 545 4 speed auto. A 7000 pound GVW car hauler is easy.

 

[HutchOven]

Our motorhome is a 1975 FMC 2900R with the original 440 Chrysler Industrial V8 and 727 3 speed auto replaced by a Cummins 5.9 24V diesel and an Allison 545 4 speed auto. A 7000 pound GVW car hauler is easy.

Power isn't the issue. Most rv's have really weak frames towards the rear because most are extended beyond the original frame. Yours being as old as it is might be built better though. Just make sure it has a full frame all the way back to the hitch with cross bracing.

You also want to make sure your hitch weight is a little on the lighter side. (9-10%) because the hitch is so far past the Axle that there is a lot of leverage and in a panic brake situation the front end can get really light and just lock up.

 

[y=mx+b]

Our motorhome is a 1975 FMC 2900R with the original 440 Chrysler Industrial V8 and 727 3 speed auto replaced by a Cummins 5.9 24V diesel and an Allison 545 4 speed auto. A 7000 pound GVW car hauler is easy.

we need pics, this thing sounds badass

 

[steven1955]

Power isn't the issue. Most rv's have really weak frames towards the rear because most are extended beyond the original frame. Yours being as old as it is might be built better though. Just make sure it has a full frame all the way back to the hitch with cross bracing.

You also want to make sure your hitch weight is a little on the lighter side. (9-10%) because the hitch is so far past the Axle that there is a lot of leverage and in a panic brake situation the front end can get really light and just lock up.

Not our coach, but looks the same. (I'll have to upload some of our pics to where I can link to them.) The FMCs were all pushers, mine now being a diesel pusher, with full size frame rails going to within one foot of the rear bumper, and there is substantial steel framing all around the rear engine compartment. Some FMCs have pulled 10,000 pound trailers, but with the original gas engine uphill towing speed can be unimpressive.

One issue we have is tongue weight due to the diesel engine putting more weight in back of the rear axle than the stock 440 gas engine did, tempered by a weight reduction program in the rear. (For example, the original 230 pound brass radiator was replaced by a custom 70 pound aluminum radiator.)

A 700 pound tongue weight with a 7000 pound GVW trailer should not be an issue, but better to use a weight distributing hitch.

Towing a trailer has the advantage of not limiting us to only being able to travel with our 4Runner. (The convertible Mustang is nice to have on some trips.) But what does one do with a 18-20 foot long carhauler when you are at an RV campground, and how safe from theft will that trailer be?

Flat towing just seems to be easier. I just would like to avoid removing and reinstalling a pair of driveshafts averaging once a day when on the road.

 

[HutchOven]

Not our coach, but looks the same. (I'll have to upload some of our pics to where I can link to them.) The FMCs were all pushers, mine now being a diesel pusher, with full size frame rails going to within one foot of the rear bumper, and there is substantial steel framing all around the rear engine compartment. Some FMCs have pulled 10,000 pound trailers, but with the original gas engine uphill towing speed can be unimpressive.

One issue we have is tongue weight due to the diesel engine putting more weight in back of the rear axle than the stock 440 gas engine did, tempered by a weight reduction program in the rear. (For example, the original 230 pound brass radiator was replaced by a custom 70 pound aluminum radiator.)

A 700 pound tongue weight with a 7000 pound GVW trailer should not be an issue, but better to use a weight distributing hitch.

Towing a trailer has the advantage of not limiting us to only being able to travel with our 4Runner. (The convertible Mustang is nice to have on some trips.) But what does one do with a 18-20 foot long carhauler when you are at an RV campground, and how safe from theft will that trailer be?

Flat towing just seems to be easier. I just would like to avoid removing and reinstalling a pair of driveshafts averaging once a day when on the road.

Yeah I figured you would be good on the frame with it being older. Mine was weak the last 5 feet and I had to brace it.

If you plan to stay at rv campgrounds, the trailer isn't the best option. I've stayed at quite a few Campgrounds that only allow the Rv and one vehicle so the trailer would be out. But some do allow 2 vehicles, you just have to plan around it. One guy I saw always brings an electric trailer dolly and maneuvers his trailer into the space and than parked his rv.

If you're stuck on keeping the 4r, look into an atlas case swap also. Significantly stronger than a fj case, a little more money, you can choose your ratio, but requires a bit more fab.

 

[steven1955]

After getting into this, meaning test driving and pricing thing like Jeeps, I have determined there are two options that merit further investigation for now:

1.) Install a front and rear driveshaft disconnect. The rear driveshaft disconnect is straightforward, which would be a standard Superior Drive line, formerly Remco, driveshaft disconnect. The front drive line disconnect would be a heavily customized Superior Drive line driveshaft disconnect with several custom one off parts. Flat towing would be done with the both driveshafts disconnected and the transmission in park.

2.). Replacing the AWD V8 specific transfer case with a V6 transfer case that has both 2WD and AWD modes, along with custom wiring to let it operate in 2WD in a V8. There would also be a rear driveshaft disconnect. Flat towing would be done with the transfer case in 2WD mode, the rear driveshaft disconnected, and the transmission in park.

I couldn't find a thread where someone swapped a V6 transfer case with 2WD mode into a V8 and have it function with all modes. Has anyone done this?

And while I am researching the above options I have not eliminated:

a.) Buying a different 4x4, or

b.) Adding a just a rear driveshaft disconnect. I would be removing the front driveshaft and disconnecting the rear driveshaft for flat towing.

 

[BlackWorksInc]

Well, the "easiest/cheapest" option would probably be just disconnecting the rear drive shaft at the rear axle and strapping it to the frame, then towing the front end on a dolly. That would leave the drivetrain static and you don't have to worry about anything other than the rear diff free-spinning.

You could do a rear driveshaft disconnect and that would work as well, but it's just four 14mm bolts and nuts back there so IMHO two `14mm wrenches and a ziplock bag are cheaper than a weird disconnect module.

Swapping an FJ case won't help you too much without disconnecting the rear driveshaft because of the way the internals of the transfer case are designed and how the fluid pump works. Not to mention you'd have to figure out all the wiring so it doesn't cause issues.

 

[Direwolf82]

If your serious about offroading and love the 4runner a transfer case swap would be best but not fast or cheap, I've been wanting to do the fj swap to get the manual transfer, makes it a little more woods/trail proof. An atlas would be shiny and all but if your not rock crawling or really stressing the unit I'm not sure I see the point to go through the trouble of fabbing up mounts and driveshafts when the fj case supposedly fits with minor alterations.
If not then disconnecting the driveshafts would be the most reliable option.
Just an FYI, locking hubs up front with the transfer that's in it now will result in no movement of the vehicle as the center diff sends all the power to the unlocked front end, or so I've been told by the transmission transfer case guy.

Sent from my SM-A516V using Tapatalk

 

[jcaino]

After getting into this, meaning test driving and pricing thing like Jeeps, I have determined there are two options that merit further investigation for now:

2.). Replacing the AWD V8 specific transfer case with a V6 transfer case that has both 2WD and AWD modes, along with custom wiring to let it operate in 2WD in a V8. There would also be a rear driveshaft disconnect. Flat towing would be done with the transfer case in 2WD mode, the rear driveshaft disconnected, and the transmission in park.

I couldn't find a thread where someone swapped a V6 transfer case with 2WD mode into a V8 and have it function with all modes. Has anyone done this?

It isn't necessarily a v6 transfer case; the manual case was also used in the gx470 as well. The swap switches it from electronic mode to manual mode, so yes, it would function with all modes.

Process is the same no matter whether its a v6 or v8 4R, here's a thread:

FJ Transfer Case Swap into a V6 4th Gen

There's other threads here and on other forums that can serve as reference, too.

If I were going to flat tow, this is absolutely the route I would go since you gain 2wd mode and not just the ability to flat tow.

If you did the cummins swap on your RV, I see no reason why you shouldn't be able to tackle this.