Outer Limits 4x4 Board

I have been thinking of putting a turbo on my 1HZ. A friend has told me that by doing so, the it will blow the output shaft on the gearbox as it was not designed for a turbo. Is this a myth or fact. Also, the mufflers have started to deteriorate so was thinking of replacing whole system. Was also told to run 3" system with extractors for better performance. Is this also myth or fact. Cheers

We have a turbo on our work cruiser. Hzj75 it runs 35s we run a 3" beaudesert exhaust system with no mufflers. It sounds horny nice whistle. We never had a issue with the output shaft but that's not sayin there isn't 1. Just sayin it hasn't happened to us.

Do a search, this has been covered SO many times......

output shaft = myth.
3inch exhaust is a must "imo".
extractors are more commonly for non turbo engines, in a turbo
application the manifold equivelent would be a tuned length turbo
manifold, kinda the same.

Thanks guys. Will do a bit more research but i might tell my mate to have another drink haha. Cheers

There was a three piece output shaft on the older r151 boxes, the output shaft coming out of the tranny was coupled to the transfer input with a loose fitting sleeve. The sleeve oly contacted about 1.5cm's iirc of the input shaft and was prone to wear and eventual stripping. Rebuilds are done with an input shaft with the sleeve built in so there is no wear.

I have an hzj79 with r151, I rebuilt the tranny and transfer and upgraded it - takes 15 pounds boost, H20 intercooler 3 inch SS mandrel bent exhaust, boost comp, ceramic coated bits.

Love it.

lshobie wrote:There was a three piece output shaft on the older r151 boxes, the output shaft coming out of the tranny was coupled to the transfer input with a loose fitting sleeve. The sleeve oly contacted about 1.5cm's iirc of the input shaft and was prone to wear and eventual stripping. Rebuilds are done with an input shaft with the sleeve built in so there is no wear.

I have an hzj79 with r151, I rebuilt the tranny and transfer and upgraded it - takes 15 pounds boost, H20 intercooler 3 inch SS mandrel bent exhaust, boost comp, ceramic coated bits.

Love it.

I'm a little lost with this mate when you say you upgraded the transfer is that just the shaft or got a whole new case from a different vehicle. ie. std 100 series

Sorry mate, I rebuilt the original tranny and transfer, i used the upgraded shaft and installed it in the transfer case - it mates up with the output shaft of the tranny. All original HZJ79 tranny and transfer.

Sorry for the confusion.

Isnt it the gear that strips the spline on the output shaft ? Seems to be the weakest part of the gbox .It is no myth that they do this .There is a modified gear that has a wider spline that slips straight on ,but pto must be removed .That was the case on my hzj 75 anyway .No turbo but 100 000 ks of towing did it.Quite a common fault hence the ready made modified gear

skip02 wrote:Isnt it the gear that strips the spline on the output shaft ? Seems to be the weakest part of the gbox .It is no myth that they do this .There is a modified gear that has a wider spline that slips straight on ,but pto must be removed .That was the case on my hzj 75 anyway .No turbo but 100 000 ks of towing did it.Quite a common fault hence the ready made modified gear

You are talking about the H55F that had that issue, not the R151.

HZJ75 has a H55F gearbox, HZJ79 has a R151 gearbox, both with 1HZ motor.

Thanks guys, you have given me plenty to go on. Will look at gearbox and find out which one it is and then take from there. Thanks heaps. Cheers