help my truck has alot of issues

[jeffmarble]

hey all i recently bought a 85 gmc k1500 4x4 and i have some issues.
first the transmission crossmember is bent bad its not salvageable and i cant use 4wd because it rubs drive shaft. Its a double hump crossmember i have a straight crossmember from i think a 84 and was curious if it would work i know i can bolt it to the stock position but it seems like the transmisson mount will be really short. i have a 700r4/np208 combo
next when in reverse hard turn ass right it clunks in rear.
my rear end also clunks when engaging it in drive reverse or shifting.

my plan was to replace the current engine with a 5.3 and 4l60 but i wasnt sure if i could mount the 208 to it.
the reason im replacing is in fairbanks alaska 2500 for a stock rebuild on a 305 is the norm i have a friend who will sell me a 99 5.3 4l60 4wd combo for 1200

[Irish_Alley]

Something don't seam right in order for your cross member to be bent to were its touching the drive shaft your frame would have to be bent to make up for the width difference. The clunking could be a bad u joint or too much play in the rear get under it and try to push the drive shaft side to side up and down see what happens (near the u joints) then twist the shaft and see how far it will turn before it locks up (with the trans in neutral) you can i get the 208 to mount to the 4l80 but it would have to be the 208 off a th400 or sm465 Not the 208 off the t350 and 700r4 they had 27 i think you would have to buy and adapter for it http://cgi.ebay.com/ebaymotors/4L80E-TRANSFER-CASE-ADAPTER-NP241-NP208-1995-96-97-_W0QQcmdZViewItemQQitemZ280543563844QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories i think this should work

[jeffmarble]

frame is bent but just were it mounts the crossmember i guess he was offroading and bent it on railroad tracks the rest of the frame is in good shape nothing else looked messed up. im guessing the crossmember just sits to low

heres crossmember i bought
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?VISuperSize&item=290410511948

heres my current crossmember
http://cgi.ebay.com/ebaymotors/84-85-86-87-GMC-JIMMY-BLAZER-Transmission-Crossmember-_W0QQcmdZViewItemQQitemZ290425567473QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

im going to have to cut the current crossmember off and try to bend back the frame rails im not to sure how to take on this job but winters coming i just got to ft wainwright ak and i heard 4wd is pretty much only option in winter with studded tires

[1980c10]

I am guessing if they're two types made then you most like need the one you already have. but use a tape measure (if you can with it bent up)and see how things match up, if they don't; then it won't work and buy the correct one. You posted a link to the correct one-why not get it?

[Irish_Alley]

what did the 84 cross member come off of the link doesn't work for me do you know the setup also

[Grim 82]

I would use the correct replacement for your bent crossmember so that you don't have to swap the trans adapter piece. They will be different heights depending on the crossmember shape. You might be able to straighten the frame with a porta-power or else see what a body shop would charge to straighten it out for you. Clunking in the rear sounds like u-joints.

[frotosride]

+1 on the u-joint but if he took a hard enough of a hit to do so much damage you mat have a little extra play in the pinion and ring gear but its hard to smash those race bearings for the pinion without almost shearing the shaft off but as many have learned in offroading anything is possible.

[VileZambonie]

The 84 crossmember and mounts are different. They are also prone to cracking so I would stick to the correct crossmember and replace your ujoints

[jeffmarble]

thanks all im trying to find a cheaper crossmember locally but alaska its really hard to come by for cheap.