Toyota tcase dilemma

rcalexander105

rcalexander105

JV Wheeler
Joined
Nov 3, 2017
Location
High Point
Rig is an 85 4Runner, 22re, W56 5-speed, stock Toyota t-case w/ 4.7 gears running 37x12.50 PBR with 4.88 R&P and elockers. I've kinda got the dual case itch but I'm curious if it's worth the coin. I already have an extra case and TG dual case cross member so would just need an adapter and F&R driveshafts (going to need a new rear anyways since I sheered mine in half this past weekend at Big Creek). I'm just wondering for east coast wheeling if I need much more than the 4.7 I already have. Would like to make it out west at some point but vast majority of the wheeling will be out here in our neck of the woods. Any and all $0.02 welcome. Thanks
 
I think you probably fine with the 4.7 case
 
It'd give you the option to use the 2.28 reduction in spots you need more wheel speed. Using both cases in low is pretty slow, really only works when it's dry.
 
Mine worked great with 39's and 5.29's in double low. I yhith 4.7's are about the same. Unless you went 39's or bigger I doubt you would use a 10 1/2:1 low range.
 
Yea, I only used 1st gear when going downhill really (never up, but it was slick this past weekend). If I needed more wheel speed I just threw it in 2nd/3rd/4th. I know it'd help the front driveline angle too b/c it's pretty steep but I think I'm torn b/t a want vs. "nice to have" at this point.
 
I was in the same situation with my old truck.(witch I believe you bought the driveline out of?) The 22r didn't have the power to spin the tires well with a stock 2.28 case, so I doubt you would use that option much with duals. 1st gear with a single 4.70 case was enough for all crawling, and I would use up to 3rd if I needed wheel speed. The only real advantage of duals to me would be helping the short front driveline angle.
 
hurt4x4 said:
I was in the same situation with my old truck.(witch I believe you bought the driveline out of?) The 22r didn't have the power to spin the tires well with a stock 2.28 case, so I doubt you would use that option much with duals. 1st gear with a single 4.70 case was enough for all crawling, and I would use up to 3rd if I needed wheel speed. The only real advantage of duals to me would be helping the short front driveline angle.
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Yep, these are your old axles and tcase. But I totally agree about the power...it's not bad w/ the 22re, but I'd really like to swap a 3rz in at some point (still going to drive it on the road some). After wheeling it for the first time with the updated driveline it's tough to say that I'd really need anything lower than the 4.7 but wanted to get folks opinions that have had both.
 
I've run both. My last rig had a 22r, 4 speed, single case with 4.70 gears, 4.10 axle gears, and 39.5" Iroks. Can't say I remember a time when I thought I needed a second case in it. 4.70s are slow enough to crawl what you need to crawl. And when you need some wheel speed, dump the clutch in 3rd gear at 3k-4k rpms.

My current rig has a 3rz, 5 speed, dual cases with 2.28 in the front and 4.70 in the rear, 4.10 axle gears and 42" stickies. Double low is really really slow. I don't use the front case that much, mostly just the rear case on obstacles. I primarily use the 2.28 gears when I'm driving the access roads from trail to trail so I can get there quicker.

A properly set up front axle/suspension, with a good front driveshaft can hold up to the driveline angle you get with a single case. In my experience/opinion, a high pinion diff is nice, but not necessary. I would save your money for the 3rz. Night and day difference compared to the 22r/re.
 
Kickdeez said:
I've run both. My last rig had a 22r, 4 speed, single case with 4.70 gears, 4.10 axle gears, and 39.5" Iroks. Can't say I remember a time when I thought I needed a second case in it. 4.70s are slow enough to crawl what you need to crawl. And when you need some wheel speed, dump the clutch in 3rd gear at 3k-4k rpms.

My current rig has a 3rz, 5 speed, dual cases with 2.28 in the front and 4.70 in the rear, 4.10 axle gears and 42" stickies. Double low is really really slow. I don't use the front case that much, mostly just the rear case on obstacles. I primarily use the 2.28 gears when I'm driving the access roads from trail to trail so I can get there quicker.

A properly set up front axle/suspension, with a good front driveshaft can hold up to the driveline angle you get with a single case. In my experience/opinion, a high pinion diff is nice, but not necessary. I would save your money for the 3rz. Night and day difference compared to the 22r/re.
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Did you do your 3rz swap? I think I'm fairly confident I could get it in the engine bay, but not sure about the wiring that goes with. I've heard the earlier distributor motors are the way to go. If you've got experience, would love your $0.02.
 
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I'm personally going duals with twin sticks so I can get my factory low gear back. I actually have my cases already on the bench and together, just need to find some time to install it. After wheeling at URE several times in a factory tcase and a 4.8 case, my opinion is the 4.8 case is too low for most things. It does ok, but its kinda a slug unless you have it in 4th gear. At windrock it would have been definitely nice to use the low factory low gear as most of the trails I rode didnt warrant the need for the 4.8 case.
 
Thanks for the discussion points I have been bouncing this same question around. I picked up a HP diff a few weeks ago but, I'm thinking dual cases now. Still working on 35' vs 37' and 4:88 vs 5:29. Lots of choices here.
 
I think I'm just going to stick w/ the single 4.7 and look forward to the 3rz.
fourtrax said:
Thanks for the discussion points I have been bouncing this same question around. I picked up a HP diff a few weeks ago but, I'm thinking dual cases now. Still working on 35' vs 37' and 4:88 vs 5:29. Lots of choices here.
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Your HP have the elocker? If so, want to sell it?
 
No sale, no eLocker but, will install an aftermarket one in it.
 
To further muddle this discussion, I was reading on someone's build where the 4.7 set was in the range box and not the rear case.

I've read about all the reasons why you shouldn't run just the range box in low w the rear in high. Seems like it might make sense for driving to the next obstacle but I'm not sure about bearing and forces exerted here and there.

There is also a bearing upgrade somewhere that a lot of guys use that's intended to eliminate the issues of running the range box in low and the rear case I high. Marlin crawler forum is where I think I got the info overload.
 
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