Mine is stabbed on the back of ToyBox. No whining!
Installing 3 speed transfer gears into a 4 speed transfer case (1 Viewer)
- Thread starter Cirbo
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Mine is stabbed on the back of ToyBox. No whining!
orangefj45
Supporting Vendor
nice work jim, keep it up!
sometimes these cases/gear sets do have noise issues but it all depends on the parts you're starting with. if the gear teeth have any rust or other damage, don't run them. if the bushings in the output gears are worn beyond spec, replace them or the gears. if the main shaft surfaces where the gears ride are worn beyond spece, replace the shaft with a good used or new unit.
gear noise coming from these cases is usually generated by the gears themselves "cantering" or "oscilating" on the main shaft which changes the contact pitch. easy enough to avoid..........i have the luxury of having a ton of parts on hand. so if i start a rebuild and find excessive wear, i just grab another donor case or a gear set i have already cleaned up and put in the parts stash. i realize that's not possible for most cruiser enthusiasts but the parts can usually be found for a reasonable price.
i'm looking forward to seeing this project progress and can't wait for you to be able to go for your first drive. keep us updated!!!!!
georg @ valley hybrids
ps: thanks for the props on the parts, i appreciate it. i have the t-case rebuild kits in stock as well.
sometimes these cases/gear sets do have noise issues but it all depends on the parts you're starting with. if the gear teeth have any rust or other damage, don't run them. if the bushings in the output gears are worn beyond spec, replace them or the gears. if the main shaft surfaces where the gears ride are worn beyond spece, replace the shaft with a good used or new unit.
gear noise coming from these cases is usually generated by the gears themselves "cantering" or "oscilating" on the main shaft which changes the contact pitch. easy enough to avoid..........i have the luxury of having a ton of parts on hand. so if i start a rebuild and find excessive wear, i just grab another donor case or a gear set i have already cleaned up and put in the parts stash. i realize that's not possible for most cruiser enthusiasts but the parts can usually be found for a reasonable price.
i'm looking forward to seeing this project progress and can't wait for you to be able to go for your first drive. keep us updated!!!!!
georg @ valley hybrids
ps: thanks for the props on the parts, i appreciate it. i have the t-case rebuild kits in stock as well.
1Fine40
Rust Buster
Please don't get me wrong on this, I was not trying to discourage your swap! I just was saying if your gears are not in excellent shape, it WILL whine more than you would like! I don't have access to lots of parts to swap out and try..(not to mention am too lazy to do that!) The Orion just met my requirements and it has been excellent, quiet, stays in gear, super crawler, I love it! You obviously know what you are doing, and have the savvy to source great parts...that's more than half the battle!!
Cheers!
Thanks for the write-up on this swap!!
I am in the process of having Safari Ltd. in Grand Junction do this exact swap for me this week for my FJ40. I do not have a press in my shop, so I was unable to do the work myself - so I think I found the best guys to do it...at a cost effective rate too.
I was wondering about the $$ invested for only a small gain on the lower gear set - but I figured it would be good insurance to rebuild it, and the 'why not while you're in there' factor for installing lower gears in the t-case.
I'll know by the weekend how loud it is, compared to my H42/4-speed tcase setup.
Thanks again for the write-up, impressive work done, can't wait to see it on the trails!
I am in the process of having Safari Ltd. in Grand Junction do this exact swap for me this week for my FJ40. I do not have a press in my shop, so I was unable to do the work myself - so I think I found the best guys to do it...at a cost effective rate too.
I was wondering about the $$ invested for only a small gain on the lower gear set - but I figured it would be good insurance to rebuild it, and the 'why not while you're in there' factor for installing lower gears in the t-case.
I'll know by the weekend how loud it is, compared to my H42/4-speed tcase setup.
Thanks again for the write-up, impressive work done, can't wait to see it on the trails!
Good write up Cirbo.
I did a variation on this about 6 years ago in my 40. I had a good H42 that came with a junk warped t.case, so to run the h42 I rebuild my J30 t.case with the transition year gear. I set everything up at the tight end of the allowable specs.
At first roadtest there was noticeable gear whine. I added a tube of molyslip and that helped a lot. After an initial break in period it was relatively quiet (and has been the last 40k miles), though now running behind an H41 instead.
I'd say worth it if you already have the parts and need to rebuild a transfer case anyways; the main additional cost in the combo is getting a transition year input gear.
I did a variation on this about 6 years ago in my 40. I had a good H42 that came with a junk warped t.case, so to run the h42 I rebuild my J30 t.case with the transition year gear. I set everything up at the tight end of the allowable specs.
At first roadtest there was noticeable gear whine. I added a tube of molyslip and that helped a lot. After an initial break in period it was relatively quiet (and has been the last 40k miles), though now running behind an H41 instead.
I'd say worth it if you already have the parts and need to rebuild a transfer case anyways; the main additional cost in the combo is getting a transition year input gear.
- Thread starter
- #47
I hadn't visited this thread in sometime, but posted a link to it on a local forum. I had forgotten the discussion about whine.
My results were beyond acceptable. The case made no additional noise over the stock unit and has been running strong for 3 years now behind a TurnKey 5.3.
My results were beyond acceptable. The case made no additional noise over the stock unit and has been running strong for 3 years now behind a TurnKey 5.3.
pbgbottle
Forum Lifer
Thanks for the update.
- Joined
- Sep 25, 2011
- Threads
- 89
- Messages
- 3,677
- Location
- Harbour City, the New Southern Wales
- Website
- www.freewayoneentertainment.com
How was the end result, as far as the low range ratio drop?
- Thread starter
- #50
The low range drop was nice. I really liked the off-road manners much better after the change. I ended up running it that way for almost 5 years, but recently changed the truck again. I switched the axles down from 4.56 to 4.11 and lost that sweet spot in the crawl for my taste. Ended up building an Orion (thanks @orangefj45!) and swapping it in for the 2.3 case. I hope to try in on the rocks in the coming weeks.
Oh, does anyone want to buy a '78 case with 2.31 low range gears installed and road tested? Also selling two complete 4.56 gear sets.
Oh, does anyone want to buy a '78 case with 2.31 low range gears installed and road tested? Also selling two complete 4.56 gear sets.
Last edited:
pb4ugo
SILVER Star
Cult45, I guess your question is asking about the differences on the crawl ratio, which comes down to a math. Keeping tire size out of the equation, but they will eventually need to be considered at some point. Trans 1st gear ratio X t/case reduction X diff gear ratio=crawl ratio. H41/4speed, stk t/case 3.55:1x1.96x4.11=28.6 or stk 4 speed w/3speed t/case gears, 3.55x2.31x4.11=33.7 It doesn't seem like much of a difference. After running stk 4speed trans and t/case for 10 yrs or more and then going to 4.88 in my diffs, It was very noticeable to me. STK 3.55x1.96x4.88=33.95 which is essentially the same result. The beauty of doing the reduction in the t/case is that your highway gearing stays the same. The other math equation is changing diff gears is probably more expensive than changing just the t/case gears. If you're looking for more crawl reduction there are a lot of different ways to go. When I went to 4:88, I knew I wanted more reduction. I changed my complete driveline soo I'm currently at 84:1 and I'm really happy with it. My driveline is now a conglomeration of different components now. It is a trail rig, with OK highway gears.
4Cruisers
SILVER Star
PM sent.
I have the the other T-Case that was built at the same time on this thread, same set-up, quiet, low miles ('79 40). For sale $400. PM gabe4jlc
